n=14
EUROCONTROL, European Organisation for the Safety of Air Navigation.
Analysis of GP-based pharmacist work system
A health board employed pharmacist had been working at a GP practice for 2 months. She worked in the practice in the mornings and at a neighbouring practice in the afternoons. One task she completed was reconciling medication changes after hospital discharge which was previously undertaken by GPs. Their introduction had not had the desired impact and a meeting was held between relevant parties who used the STEW principles to reach a shared understanding of the system and design system improvements. | |
Foundation concept | Purpose of system Agree boundaries |
Seek multiple perspectives | Practice-based pharmacist GPs GP administrative staff (including the practice manage) Patient representative Community pharmacists Local pharmacy clinical lead Secondary care representative (a pharmacist who was usually based on an acute medical ward) |
Consider work conditions | Demand/capacity Resources Constraints Leading indicators |
Analyse interactions and flow | Interactions and flow |
Understand why decisions make sense at the time | |
Explore performance variability | GPs and the pharmacist discussed the different ways they completed medication reconciliation and identified workarounds and trade-offs that would help achieve the goals of the system (reduced workload and increased quality). |
GP, general practitioner; STEW, Systems Thinking for Everyday Work.
The foundation concept acknowledges that ‘ most healthcare problems and solutions belong to the system ’. This emphasises that the aim of applying a systems approach is to improve overall system functioning and not the functioning of one individual component within a system. For example, improving clinical assessments will not improve overall system performance unless patients can access assessments appropriately.
All systems interact with other systems, but out of necessity those analysing the system need to agree boundaries for the analysis. This may mean the GP practice building, a single hospital ward, the emergency department, a pharmacy or nursing home. Despite this, it is important to remember that external factors will influence the system under study and changes may have effects in parts of the system outside the boundary.
Appreciate that people, at all organisational levels and regardless of responsibilities and hierarchical status, are the local experts in the work they do. Exploring the different perspectives held by these people, especially in relation to the other principles, is crucial when analysing incidents and designing and implementing change.
Obtaining multiple perspectives allows an exploration of variability in demand and capacity, availability of resources (such as information or physical resources) and constraints (such as guidance that directs work to be performed in a particular way). These considerations can help identify leading indicators of impending trouble by identifying where demand may exceed capacity or where resources may not be available. Multiple perspectives can also help explore how work conditions affect staff well-being (eg, health, safety, motivation, job satisfaction, comfort, joy at work) and performance (eg, care quality, safety, productivity, effectiveness, efficiency).
System outputs are dependent on the constantly changing interactions between people, tasks, equipment and the wider environment. Multiple perspectives on system functioning help explore interactions to better understand the effects of actions and proposed changes on other parts of the system. Examining flow of work can help identify how these interactions and the conditions of work contribute to bottlenecks and blockages.
This principle directs us that, when looking back on individual, team or organisational decision-making, we should appreciate that people do what makes sense to them based on the system conditions experienced at the time (demand, capacity, resources and constraints), interactions and flow of work. It is easy (and common) to look back with hindsight to blame or judge individual components (usually humans) and recommend change such as refresher training and punitive actions. This must consider why such decisions were made, or change is unlikely to be effective. The same conditions may occur again, and the same decision may need to be made to continue successful system functioning. By exploring why decisions were made, we move beyond blaming ‘human error’ which can help promote a ‘Just Culture’—where staff are not punished for actions that are in keeping with their experience and training and which were made to cope with the work conditions faced at the time. 35
As work conditions and interactions change rapidly and often in an unpredicted manner, people adapt what they do to achieve successful outcomes. They make trade-offs, such as efficiency thoroughness trade-offs, and use workarounds to cope with the conditions they face. In retrospect these could be seen as ‘errors’, but are often adaptations used to cope with unplanned or unexpected system conditions. They result in a difference between work-as-done and work-as-imagined and define everyday work from which outcomes, both good and bad, emerge.
The included case report describes the practical application of these principles to understand work within a system and the subsequent design of organisational change ( table 3 ). The presented details are a small part of a larger project in which the authors (DM, PB and SL) were involved. The new appointment of a health board employed pharmacist to a general practice had not had the anticipated impact and there had been unexpected effects. The GPs had hoped for a greater reduction in workload quantity, the health board had hoped for increased formulary compliance and there had been increased workload in secondary care.
Traditional ways of exploring this problem may include working backwards from the problem to identify an area for improvement. In this case, further training of the pharmacist may have been suggested and targets may have been introduced in relation to workload or formulary compliance. However, without understanding why the pharmacist worked this way, it is likely any retraining or change would be ineffective. The STEW principles provided a framework to analyse the problem from a systems perspective, understand what influenced the pharmacist’s decisions and explore the effects of these decisions elsewhere in the system. Obtaining multiple perspectives identified that the pharmacist had to trade off between competing goals (productivity vs thoroughness including safety and formulary compliance). The application of the principles identified how pharmacists varied their approach to increase productivity while remaining safe. Learning from this everyday work helped bring work-as-done and work-as-imagined closer and several changes to improve system performance were identified and implemented.
This ensured pharmacists had the information needed to complete the task ( System condition—resources ). It also reduced work in other sectors ( Interactions ) and increased the efficiency of task completion and so reduced delays for patients ( Flow ).
The timetable for the week was changed to prioritise other prescribing tasks at the start of the week and complete medication reconciliation later in the week ( System condition—capacity/demand ). Through discussion of system conditions, the pharmacist identified that certain discharges took longer to complete, resulted in further contact with the practice (with a resultant increased GP workload) or had an increased risk of patient harm. Discharges that included these factors were prioritised and completed early in the week in attempt to mitigate these problems.
Protocols were changed to have minimum specification to allow local adaptation by pharmacists ( System conditions—constraints ). This supported the pharmacists to employ a variety of responses dependent on the context ( Performance Variability ) which reduced pharmacists’ concerns of blame if they did not follow the protocol ( Understand why decision made sense ). For example, after a short admission where it was unlikely medication was changed, pharmacists did not need to contact secondary care regarding medication not recorded on the discharge letter ( Understand why decision made sense ). If they felt they did have to check, the option of contacting the patient was included. Similarly, the need to contact all patients after discharge was removed. Pharmacists could use other options such as contacting the community pharmacy if more appropriate ( Performance Variability ).
Regular GP mentoring sessions were included as pharmacists’ found discussing cases with GPs allowed them to consider the benefits and potential problems of their actions in other parts of the system (Interactions and Performance Variability ). For example, not limiting the number of times certain medication can be issued but instead ensuring practice systems for monitoring are used. This also allowed them to consider when they needed to be more thorough at the expense of efficiency ( Performance Variability ), for example, when there were leading indicators of problems such as high-risk medication.
This paper describes the adaptation and redesign of previously developed system principles for generic application in healthcare settings. The STEW principles underpin and are characteristic of a holistic systems approach. The case report demonstrates application of the principles to analyse a care system and to subsequently design change through understanding current work processes, predicting system behaviour and designing modifications to improve system performance.
We propose that the STEW principles can be used as a framework for teams to analyse, learn and improve from unintended outcomes, reports of excellent care and routine everyday work ‘hassles’. 36 37 The overall focus is on team and organisational learning by, for example, small group discussion to promote a deep understanding of ‘how everyday work is actually done’ (rather than just fixating on things that go wrong). This allows an exploration of the system conditions that result in the need for people to vary how they work; the identification and sharing of successful adaptations and an understanding of the effect of adaptations elsewhere in the system (mindful adaptation). From this, we can decide if variation is useful (and thus support staff in doing this effectively) or unwanted (and system conditions can then be considered to try to damp variation). These discussions can help reconcile work-as-done and work-as-imagined . Although, as conditions change unpredictably, new ways of working will continue to evolve and so we must continue to explore and share learning from everyday work, not just when something goes wrong.
The focus of safety efforts, in incident investigation and other QI activity, is often on identifying things that have gone wrong and implementing change to prevent ‘error’ recurring. 20 The focus is often on the ‘root causes’ of adverse events or categorising events most likely to cause systems to fail (eg, using Pareto charts). 20 38 This linear ‘cause and effect’ thinking can lead to single components, deemed to be the ‘cause’ of the unwanted event or care problem, being prioritised for improvement. Although this may improve the performance of that component it may not improve overall system functioning and, due to the complex interactions in healthcare systems, may generate unwanted unintended consequences. The principles promote examining and treating the relevant system as a whole which may strengthen the way we conduct incident investigation and how we design QI projects.
To successfully align corrective actions or improvement interventions with contributing factors, and therefore ensure actions have the desired effect, a deep understanding of everyday work is essential. 39 Methods such as process mapping are often promoted to explore how systems work which, when used properly, can be a useful method to aid healthcare improvers. To more closely model and understand work-as-done , the STEW principles could be considered to show the influences on components that affect performance such as feedback loops, coupling to other components and internal and external influences.
The STEW principles may also support another commonly used QI method: Plan, Do, Study, Act cycles. 40 It has been suggested that more in-depth work is often required in the planning and study stages of improvement activity, especially when dealing with complex problems. 40 The application of the principles may help explore factors that will influence change (such as resources, interactions with other parts of the systems and personal and organisational goals). Similarly, during the study phase, the principles can help explore how system properties prompted people to act the way they did. This level of understanding can then inform further iterative cycles.
Patient care is often delivered by teams across interfaces of care which further increases complexity. 41 It is estimated that only around half to three-quarters of actions recommended after incident analysis are implemented. 21 Although this is often due to a lack of shared learning and local action plans and involvement of key stakeholders, 21 those investigating such cases may feel unable to influence change in such a complex environment. This may result on a focus on what is perceived as manageable or feasible changes to single processes. Obtaining multiple perspective on work and improvement encourages a team-based approach to learning and change but systems are still required to ensure learning and action plans are shared. Although the principles have been used in incident investigation and to influence organisational change across care interfaces, simply introducing a set of principles alone will not improve the likelihood of the implementation of effective system-level change. 42 43 Training on, and evaluation of, the application of the principles is required.
Understanding how safety is created and maintained must involve more than examining when it fails. Improvement interventions often aim to standardise and simplify current processes. Although these approaches are important, in a resource-limited environment, it will never be possible to implement organisational change to fix all system problems. Even if this was possible, as systems evolve with new treatments and technology, conditions will emerge that have not been considered. To optimise success in complex systems, the contribution of humans to creating safety needs to be explored, understood and enhanced. 44 Human adaptation is always required to ensure safe working and needs to be understood, appreciated and supported. Studying systems using the principles may support workers who make such adaptations to be more mindful of wider system effects.
There is growing interest in healthcare in how we can learn more from how people create safety. The Learning from Excellence movement promotes learning and improvement from the analysis of peer-reported episodes of excellent care and positive deviancy aims to identify how some people excel despite facing the same constraints as others. 36 45 The Safety-II systems approach that influenced these principles is similar in that it focuses on how people help to create safety by adapting to unplanned system factors and interactions.
By understanding why decisions are made, the application of the principles supports the development of a ‘Just Culture’—indeed this was one of EUROCONTROL’s original principles and was incorporated into the principle, ‘Understand why decisions make sense at the time’. A ‘Just Culture’ has been described as ‘a culture of trust, learning and accountability’, where people are willing to report incidents where something has gone wrong, as they know it will inform learning to improve care and not be used to assign blame inappropriately. 35 Our approach aims to avoid unwarranted blame and increase healthcare staff support and learning when something has gone wrong. 46 47 Furthermore, application of the principles may empower staff and patients to not just report incidents but contribute to analysis and become integral parts of the improvement process through coproduction of safer systems. Obtaining the perspective of the patient when applying the principles is critical to understanding and improving systems as they are often the only constant when care crosses interfaces. This type of approach to improvement is strongly promoted and may avoid short-sighted responses to patient safety incidents (eg, refresher training or new protocols) and result in the design of better, and more cost-effective care systems. 48
Alternative methods exist for modelling and understanding complex systems, such as the Functional Resonance Analysis Method, 49 and a complex systems approach is used in accident models such as the Systems Theoretic Accident Modelling and Processes 50 and AcciMAPs. 51 These robust methods for system analysis are difficult for front-line teams to implement without specialised training. 29 The principles, on the other hand, were designed with front-line healthcare workers in order to allow non-experts to be able to adopt this type of thinking to understand and improve systems. The influence of conditions of work, including organisational and external factors, on safety has been appreciated for some time and is included in other models used in healthcare to explore safety in complex systems. 52–54 The Systems Engineering Initiative for Patient Safety (SEIPS) model is arguably one of the best known systems-based frameworks in healthcare. 53 While this model promotes seeking multiple perspectives to describe the interactions between components, the STEW principles focus on how these interactions influence the way work is done and thus may complement the use of the SEIPS model.
Any consensus method can produce an agreed outcome, but that does not mean these are wholly adequate in terms of validity, feasibility or transferability. Only 15 participants were involved in the initial development with 32 more in workshops; however, a wide range of professions with significant patient safety and QI experience were recruited. The appraiser workshop was attended by both primary and secondary care doctors, and other staff groups. Their comments were used to further refine the principles, but no attempt was made to assess their agreement on the importance and applicability of principles. The principles have not been shown in practice to improve performance, and further research and evaluation of their application in various sectors of healthcare is needed.
Systems thinking is essential for examining and improving healthcare safety and performance, but a shared understanding and application of the concept is not well developed among front-line staff, healthcare improvers, leaders, policymakers, the media and the general public. It is a complicated topic and requires an understandable framework for practical application by the care workforce. The developed principles may aid a deeper exploration of system safety in healthcare as part of learning from problematic situations, everyday work and excellent practices. They may also inform more effective design of local improvement interventions. Ultimately, the principles help define what a ‘systems approach’ actually entails in a practical sense within the healthcare context.
Under UK ‘Governance Arrangements for Research Ethics Committees’, ethical research committee review is not required for service evaluation or research which, for example, seeks to elicit the views, experiences and knowledge of healthcare professionals on a given subject area. 55 Similarly ‘service evaluation’ that involves NHS staff recruited as research participants by virtue of their professional roles also does not require ethical review from an established NHS research ethics committee.
The authors thank all those who contributed to the adaptation of the principles and Michael Cannon for his comments from a service user’s perspective.
Twitter: @duncansmcnab, @pbnes
Contributors: DM, JM and PB conceived the project. SS developed the original principles and led the consensus building workshop. DM and SL collected the data. DM, SL, SS, JM and PB analysed the feedback to adapt the principles. DM drafted the original report and SL, SS and JM revised and agreed on the final manuscript.
Funding: The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests: None declared.
Patient and public involvement: Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research.
Patient consent for publication: Not required.
Provenance and peer review: Not commissioned; externally peer reviewed.
Data availability statement: Data are available upon reasonable request. Data are available upon request relating to the stages of the consensus building process.
Remember back to the time when we were in high school science class. Our teachers had a framework for helping us learn – an experimental approach based on the best available evidence at hand. We were asked to make observations about the world around us, then attempt to form an explanation or hypothesis to explain what we had observed. We then tested this hypothesis by predicting an outcome based on our theory that would be achieved in a controlled experiment – if the outcome was achieved, we had proven our theory to be correct.
We could then apply this learning to inform and test other hypotheses by constructing more sophisticated experiments, and tuning, evolving or abandoning any hypothesis as we made further observations from the results we achieved.
Experimentation is the foundation of the scientific method, which is a systematic means of exploring the world around us. Although some experiments take place in laboratories, it is possible to perform an experiment anywhere, at any time, even in software development.
Practicing Hypothesis-Driven Development is thinking about the development of new ideas, products and services – even organizational change – as a series of experiments to determine whether an expected outcome will be achieved. The process is iterated upon until a desirable outcome is obtained or the idea is determined to be not viable.
We need to change our mindset to view our proposed solution to a problem statement as a hypothesis, especially in new product or service development – the market we are targeting, how a business model will work, how code will execute and even how the customer will use it.
We do not do projects anymore, only experiments. Customer discovery and Lean Startup strategies are designed to test assumptions about customers. Quality Assurance is testing system behavior against defined specifications. The experimental principle also applies in Test-Driven Development – we write the test first, then use the test to validate that our code is correct, and succeed if the code passes the test. Ultimately, product or service development is a process to test a hypothesis about system behaviour in the environment or market it is developed for.
The key outcome of an experimental approach is measurable evidence and learning.
Learning is the information we have gained from conducting the experiment. Did what we expect to occur actually happen? If not, what did and how does that inform what we should do next?
In order to learn we need use the scientific method for investigating phenomena, acquiring new knowledge, and correcting and integrating previous knowledge back into our thinking.
As the software development industry continues to mature, we now have an opportunity to leverage improved capabilities such as Continuous Design and Delivery to maximize our potential to learn quickly what works and what does not. By taking an experimental approach to information discovery, we can more rapidly test our solutions against the problems we have identified in the products or services we are attempting to build. With the goal to optimize our effectiveness of solving the right problems, over simply becoming a feature factory by continually building solutions.
The steps of the scientific method are to:
We need to challenge the concept of having fixed requirements for a product or service. Requirements are valuable when teams execute a well known or understood phase of an initiative, and can leverage well understood practices to achieve the outcome. However, when you are in an exploratory, complex and uncertain phase you need hypotheses.
Handing teams a set of business requirements reinforces an order-taking approach and mindset that is flawed.
Business does the thinking and ‘knows’ what is right. The purpose of the development team is to implement what they are told. But when operating in an area of uncertainty and complexity, all the members of the development team should be encouraged to think and share insights on the problem and potential solutions. A team simply taking orders from a business owner is not utilizing the full potential, experience and competency that a cross-functional multi-disciplined team offers.
The traditional user story framework is focused on capturing requirements for what we want to build and for whom, to enable the user to receive a specific benefit from the system.
As A…. <role>
I Want… <goal/desire>
So That… <receive benefit>
Behaviour Driven Development (BDD) and Feature Injection aims to improve the original framework by supporting communication and collaboration between developers, tester and non-technical participants in a software project.
In Order To… <receive benefit>
As A… <role>
When viewing work as an experiment, the traditional story framework is insufficient. As in our high school science experiment, we need to define the steps we will take to achieve the desired outcome. We then need to state the specific indicators (or signals) we expect to observe that provide evidence that our hypothesis is valid. These need to be stated before conducting the test to reduce biased interpretations of the results.
If we observe signals that indicate our hypothesis is correct, we can be more confident that we are on the right path and can alter the user story framework to reflect this.
Therefore, a user story structure to support Hypothesis-Driven Development would be;
What functionality we will develop to test our hypothesis? By defining a ‘test’ capability of the product or service that we are attempting to build, we identify the functionality and hypothesis we want to test.
What is the expected outcome of our experiment? What is the specific result we expect to achieve by building the ‘test’ capability?
What signals will indicate that the capability we have built is effective? What key metrics (qualitative or quantitative) we will measure to provide evidence that our experiment has succeeded and give us enough confidence to move to the next stage.
The threshold you use for statistically significance will depend on your understanding of the business and context you are operating within. Not every company has the user sample size of Amazon or Google to run statistically significant experiments in a short period of time. Limits and controls need to be defined by your organization to determine acceptable evidence thresholds that will allow the team to advance to the next step.
For example if you are building a rocket ship you may want your experiments to have a high threshold for statistical significance. If you are deciding between two different flows intended to help increase user sign up you may be happy to tolerate a lower significance threshold.
The final step is to clearly and visibly state any assumptions made about our hypothesis, to create a feedback loop for the team to provide further input, debate and understanding of the circumstance under which we are performing the test. Are they valid and make sense from a technical and business perspective?
Hypotheses when aligned to your MVP can provide a testing mechanism for your product or service vision. They can test the most uncertain areas of your product or service, in order to gain information and improve confidence.
Examples of Hypothesis-Driven Development user stories are;
We Believe That increasing the size of hotel images on the booking page
Will Result In improved customer engagement and conversion
We Will Know We Have Succeeded When we see a 5% increase in customers who review hotel images who then proceed to book in 48 hours.
It is imperative to have effective monitoring and evaluation tools in place when using an experimental approach to software development in order to measure the impact of our efforts and provide a feedback loop to the team. Otherwise we are essentially blind to the outcomes of our efforts.
In agile software development we define working software as the primary measure of progress.
By combining Continuous Delivery and Hypothesis-Driven Development we can now define working software and validated learning as the primary measures of progress.
Ideally we should not say we are done until we have measured the value of what is being delivered – in other words, gathered data to validate our hypothesis.
Examples of how to gather data is performing A/B Testing to test a hypothesis and measure to change in customer behaviour. Alternative testings options can be customer surveys, paper prototypes, user and/or guerrilla testing.
One example of a company we have worked with that uses Hypothesis-Driven Development is lastminute.com . The team formulated a hypothesis that customers are only willing to pay a max price for a hotel based on the time of day they book. Tom Klein, CEO and President of Sabre Holdings shared the story of how they improved conversion by 400% within a week.
Combining practices such as Hypothesis-Driven Development and Continuous Delivery accelerates experimentation and amplifies validated learning. This gives us the opportunity to accelerate the rate at which we innovate while relentlessly reducing cost, leaving our competitors in the dust. Ideally we can achieve the ideal of one piece flow: atomic changes that enable us to identify causal relationships between the changes we make to our products and services, and their impact on key metrics.
As Kent Beck said, “Test-Driven Development is a great excuse to think about the problem before you think about the solution”. Hypothesis-Driven Development is a great opportunity to test what you think the problem is, before you work on the solution.
Olivia Guy-Evans, MSc
Associate Editor for Simply Psychology
BSc (Hons) Psychology, MSc Psychology of Education
Olivia Guy-Evans is a writer and associate editor for Simply Psychology. She has previously worked in healthcare and educational sectors.
Learn about our Editorial Process
Saul McLeod, PhD
Editor-in-Chief for Simply Psychology
BSc (Hons) Psychology, MRes, PhD, University of Manchester
Saul McLeod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.
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Bronfenbrenner’s ecological systems theory posits that an individual’s development is influenced by a series of interconnected environmental systems, ranging from the immediate surroundings (e.g., family) to broad societal structures (e.g., culture).
These systems include the microsystem, mesosystem, exosystem, macrosystem, and chronosystem, each representing different levels of environmental influences on an individual’s growth and behavior.
Bronfenbrenner (1977) suggested that the child’s environment is a nested arrangement of structures, each contained within the next. He organized them in order of how much of an impact they have on a child.
He named these structures the microsystem, mesosystem, exosystem, macrosystem and the chronosystem.
Because the five systems are interrelated, the influence of one system on a child’s development depends on its relationship with the others.
The microsystem is the first level of Bronfenbrenner’s theory and is the things that have direct contact with the child in their immediate environment.
It includes the child’s most immediate relationships and environments. For example, a child’s parents, siblings, classmates, teachers, and neighbors would be part of their microsystem.
Relationships in a microsystem are bi-directional, meaning other people can influence the child in their environment and change other people’s beliefs and actions. The interactions the child has with these people and environments directly impact development.
The child is not just a passive recipient but an active contributor in these bidirectional interactions.
Example: Supportive parents who read to their child and provide educational activities may positively influence cognitive and language skills. Or, children with friends who bully them at school might develop self-esteem issues.
The mesosystem is where a person’s individual microsystems do not function independently but are interconnected and assert influence upon one another.
The mesosystem involves interactions between different microsystems in the child’s life. These interactions can have significant impacts on the child’s development.
Example: A child whose parents are actively involved in their school life, such as attending parent-teacher conferences and volunteering for school events, may perform better academically.
This is because the interaction between the family microsystem and the school microsystem (forming the mesosystem) creates a supportive environment for learning.
Another example could be the interaction between a child’s peer group and family. If a child’s friends value academic achievement, this attitude might influence the child’s behavior at home, leading to more time spent on homework and studying.
The exosystem is a component of the ecological systems theory developed by Urie Bronfenbrenner in the 1970s.
It incorporates other formal and informal social structures such as local governments, friends of the family, and mass media.
While not directly interacting with the child, the exosystem still influences the microsystems.
Example: A parent’s workplace policies can significantly affect a child’s development. If a company offers flexible working hours or work-from-home options, parents might have more time to spend with their children, positively impacting the child’s emotional development and family relationships.
Another example could be local government decisions. If a city council decides to close down a community center or library due to budget cuts, this could limit a child’s access to educational resources and after-school activities, potentially affecting their academic and social development.
The macrosystem focuses on how cultural elements affect a child’s development, consisting of cultural ideologies, attitudes, and social conditions that children are immersed in.
Beliefs about gender roles, individualism, family structures, and social issues establish norms and values that permeate a child’s microsystems.
The macrosystem differs from the previous ecosystems as it does not refer to the specific environments of one developing child but the already established society and culture in which the child is developing.
Example: In a society that highly values individual achievement, children might be encouraged to be more competitive and self-reliant.
This could influence parenting styles in the microsystem, with parents focusing more on personal accomplishments and independence.
Conversely, in a culture that emphasizes collective harmony, children might be raised to prioritize group needs over individual desires.
This could manifest in the microsystem as parents encouraging more cooperative play and shared decision-making among siblings.
The fifth and final level of Bronfenbrenner’s ecological systems theory is known as the chronosystem.
The chronosystem relates to shifts and transitions over the child’s lifetime. These environmental changes can be predicted, like starting school, or unpredicted, like parental divorce or changing schools when parents relocate for work, which may cause stress.
Aging itself interacts with shifting social expectations over the lifespan within the chronosystem.
How children respond to expected and unexpected life transitions depends on the support of their ecological systems.
Example: The introduction of widespread internet access and social media represents a significant chronosystem change for many children.
This technological shift has altered how children interact with peers, access information, and spend their leisure time, potentially affecting their social skills, cognitive development, and even sleep patterns.
Another example could be a major historical event like a global pandemic.
Children growing up during such a time might experience disruptions in their education (shift to online learning), changes in family dynamics (parents working from home), and altered social interactions (social distancing), all of which can have long-lasting effects on their development.
Microsystem | • Immediate family (parents, siblings, grandparents) • School environment (teachers, classmates) • Peer group and close friends • Extracurricular activities (sports teams, clubs) • Healthcare providers (pediatrician, dentist) • Neighborhood playmates • Childcare arrangements |
Mesosystem | • Parent-teacher communication • Family-peer group interactions • School-neighborhood connections • Family-healthcare provider relationships • Interactions between different friend groups • Family-extracurricular activity connections • Religious community-family interactions |
Exosystem | • Parents’ workplaces and policies • Extended family networks • Local community organizations • School board decisions • Social services and support systems • Mass media and social media • Local government policies • Public transportation systems |
Macrosystem | • Cultural norms and expectations • Socioeconomic factors • Educational policies and standards • Healthcare systems • Technological advancements • Environmental attitudes and policies • Gender roles and expectations • Religious or philosophical ideologies |
Chronosystem | • Major historical events (e.g., pandemics, wars) • Technological shifts (e.g., rise of internet, social media) • Changes in family structure (e.g., divorce, remarriage) • Educational reforms • Economic cycles (booms and recessions) • Climate change and environmental shifts • Generational cultural changes • Personal life transitions (e.g., puberty, starting school) |
It is important to note that Bronfenbrenner (1994) later revised his theory and instead named it the ‘Bioecological model’.
Bronfenbrenner became more concerned with the proximal development processes, meaning the enduring and persistent forms of interaction in the immediate environment.
His focus shifted from environmental influences to developmental processes individuals experience over time.
‘…development takes place through the process of progressively more complex reciprocal interactions between an active, evolving biopsychological human organism and the persons, objects, and symbols in its immediate external environment.’ ( Bronfenbrenner, 1995 ).
Bronfenbrenner also suggested that to understand the effect of these proximal processes on development, we have to focus on the person, context, and developmental outcome, as these processes vary and affect people differently.
While his original ecological systems theory emphasized the role of environmental systems, his later bioecological model focused more closely on micro-level interactions.
The bioecological shift highlighted reciprocal processes between the actively evolving individual and their immediate settings. This represented an evolution in Bronfenbrenner’s thinking toward a more dynamic developmental process view.
However, the bioecological model still acknowledged the broader environmental systems from his original theory as an important contextual influence on proximal processes.
The bioecological focus on evolving person-environment interactions built upon the foundation of his ecological systems theory while bringing developmental processes to the forefront.
The Ecological Systems Theory has been used to link psychological and educational theory to early educational curriculums and practice. The developing child is at the center of the theory, and all that occurs within and between the five ecological systems is done to benefit the child in the classroom.
There are lots of studies that have investigated the effects of the school environment on students. Below are some examples:
Lippard et al. (2017) conducted a study to test Bronfenbrenner’s theory. They investigated the teacher-child relationships through teacher reports and classroom observations.
They found that these relationships were significantly related to children’s academic achievement and classroom behavior, suggesting that these relationships are important for children’s development and supports the Ecological Systems Theory.
Wilson et al. (2002) found that creating a positive school environment through a school ethos valuing diversity has a positive effect on students’ relationships within the school. Incorporating this kind of school ethos influences those within the developing child’s ecological systems.
Langford et al. (2014) found that whole-school approaches to the health curriculum can positively improve educational achievement and student well-being. Thus, the development of the students is being affected by the microsystems.
Bronfenbrenner’s model quickly became very appealing and accepted as a useful framework for psychologists, sociologists, and teachers studying child development.
The ecological systems theory is thought to provide a holistic approach that includes all the systems children and their families are involved in, reflecting the dynamic nature of actual family relationships.
Paat (2013) considers how Bronfenbrenner’s theory is useful when it comes to the development of immigrant children. They suggest that immigrant children’s experiences in the various ecological systems are likely to be shaped by their cultural differences.
Understanding these children’s ecology can aid in strengthening social work service delivery for these children.
A limitation of the Ecological Systems Theory is that there is limited research examining the mesosystems, mainly the interactions between neighborhoods and the family of the child. Therefore, the extent to which these systems can shape child development is unclear.
Another limitation of Bronfenbrenner’s theory is that it is difficult to empirically test the theory. The studies investigating the ecological systems may establish an effect, but they cannot establish whether the systems directly cause such effects.
Furthermore, this theory can lead to assumptions that those who do not have strong and positive ecological systems lack in development.
Whilst this may be true in some cases, many people can still develop into well-rounded individuals without positive influences from their ecological systems.
For instance, it is not true to say that all people who grow up in poverty-stricken areas of the world will develop negatively. Similarly, if a child’s teachers and parents do not get along, some children may not experience any negative effects if it does not concern them.
As a result, people should try to avoid making broad assumptions about individuals using this theory.
Bronfenbrenner’s theory of human development has undergone significant evolution since its inception in the 1970s, raising questions about its current relevance and application.
Initially conceptualized as an ecological model focused primarily on contextual influences, it matured into a more sophisticated bioecological model emphasizing the critical role of proximal processes in development.
The mature version of the theory, often referred to as the bioecological model, places proximal processes at its core.
These processes are defined as “enduring forms of interaction in the immediate environment” and are considered the primary engines of development.
Central to the mature theory is the Process-Person-Context-Time (PPCT) model . This model emphasizes the interplay between four key elements:
Despite these advancements, the theory’s relevance in the 21st century has been a subject of debate. Kelly and Coughlan (2019) found significant links between Bronfenbrenner’s ecological systems theory and contemporary frameworks for youth mental health recovery.
Their research suggests that the components of mental health recovery are embedded in an “ecological context of influential relationships,” aligning with Bronfenbrenner’s emphasis on the importance of interconnected environmental systems.
However, the rapid technological advancements of the 21st century have raised questions about how well Bronfenbrenner’s theory accommodates these changes.
The theory’s relevance is further challenged by common misapplications in contemporary research.
Many scholars continue to apply outdated versions or misinterpret key concepts when claiming to use Bronfenbrenner’s theory, as pointed out by other scholars .
These misapplications often involve focusing solely on contextual influences without considering proximal processes, or failing to account for the time dimension in research designs.
Despite these challenges, Bronfenbrenner’s theory remains a valuable framework for understanding human development in the 21st century.
Its comprehensive nature allows for the examination of development in various contexts and across different life stages.
The theory’s emphasis on the interplay between individual characteristics, environmental influences, and temporal factors provides a nuanced approach to understanding the complexities of modern human development.
To maintain its relevance, researchers and practitioners must understand the theory’s evolution and apply it correctly.
This involves recognizing the centrality of proximal processes, considering the role of technology in developmental contexts, and designing studies that capture the dynamic nature of development over time.
By adapting the theory to include modern contexts while maintaining its core principles, Bronfenbrenner’s bioecological model can continue to provide valuable insights into human development in the 21st century and beyond.
Navarro & Tudge (2022) proposed the neo-ecological theory, an adaptation of the bioecological theory. Below are their main ideas for updating Bronfenbrenner’s theory to the technological age:
Urie Bronfenbrenner was born in Moscow, Russia, in 1917 and experienced turmoil in his home country as a child before immigrating to the United States at age 6.
Witnessing the difficulties faced by children during the unrest and rapid social change in Russia shaped his ideas about how environmental factors can influence child development.
Bronfenbrenner went on to earn a Ph.D. in developmental psychology from the University of Michigan in 1942.
At the time, most child psychology research involved lab experiments with children briefly interacting with strangers.
Bronfenbrenner criticized this approach as lacking ecological validity compared to real-world settings where children live and grow. For example, he cited Mary Ainsworth’s 1970 “Strange Situation” study , which observed infants with caregivers in a laboratory.
Bronfenbrenner argued that these unilateral lab studies failed to account for reciprocal influence between variables or the impact of broader environmental forces.
His work challenged the prevailing views by proposing that multiple aspects of a child’s life interact to influence development.
In the 1970s, drawing on foundations from theories by Vygotsky, Bandura, and others acknowledging environmental impact, Bronfenbrenner articulated his groundbreaking Ecological Systems Theory.
This framework mapped children’s development across layered environmental systems ranging from immediate settings like family to broad cultural values and historical context.
Bronfenbrenner’s ecological perspective represented a major shift in developmental psychology by emphasizing the role of environmental systems and broader social structures in human development.
The theory sparked enduring influence across many fields, including psychology, education, and social policy.
What is the main contribution of bronfenbrenner’s theory.
The Ecological Systems Theory has contributed to our understanding that multiple levels influence an individual’s development rather than just individual traits or characteristics.
Bronfenbrenner contributed to the understanding that parent-child relationships do not occur in a vacuum but are embedded in larger structures.
Ultimately, this theory has contributed to a more holistic understanding of human development, and has influenced fields such as psychology, sociology, and education.
If a child experiences conflict or neglect within their family, or bullying or rejection by their peers, their microsystem may break down. This can lead to a range of negative outcomes, such as decreased academic achievement, social isolation, and mental health issues.
Additionally, if the microsystem is not providing the necessary support and resources for the child’s development, it can hinder their ability to thrive and reach their full potential.
The ecological systems theory explains peer pressure as a result of the microsystem (immediate environment) and mesosystem (connections between environments) levels.
Peers provide a sense of belonging and validation in the microsystem, and when they engage in certain behaviors or hold certain beliefs, they may exert pressure on the child to conform. The mesosystem can also influence peer pressure, as conflicting messages and expectations from different environments can create pressure to conform.
Bronfenbrenner, U. (1974). Developmental research, public policy, and the ecology of childhood . Child development, 45 (1), 1-5.
Bronfenbrenner, U. (1977). Toward an experimental ecology of human development . American psychologist, 32 (7), 513.
Bronfenbrenner, U. (1979). The ecology of human development: Experiments by nature and design. Harvard University Press.
Bronfenbrenner, U. (1995). Developmental ecology through space and time: A future perspective .
Bronfenbrenner, U., & Evans, G. W. (2000). Developmental science in the 21st century: Emerging questions, theoretical models, research designs and empirical findings . Social development, 9 (1), 115-125.
Bronfenbrenner, U., & Ceci, S. J. (1994). Nature-nurture reconceptualised: A bio-ecological model . Psychological Review, 10 (4), 568–586.
Bronfenbrenner, U., & Morris, P. A. (1998). The ecology of developmental processes. In W. Damon & R. M. Lerner (Eds.), Handbook of child psychology: Theoretical models of human development (5th ed., pp. 993–1028). John Wiley & Sons, Inc..
Hayes, N., O’Toole, L., & Halpenny, A. M. (2017). Introducing Bronfenbrenner: A guide for practitioners and students in early years education . Taylor & Francis.
Kelly, M., & Coughlan, B. (2019). A theory of youth mental health recovery from a parental perspective . Child and Adolescent Mental Health, 24 (2), 161-169.
Langford, R., Bonell, C. P., Jones, H. E., Pouliou, T., Murphy, S. M., Waters, E., Komro, A. A., Gibbs, L. F., Magnus, D. & Campbell, R. (2014). The WHO Health Promoting School framework for improving the health and well‐being of students and their academic achievement . Cochrane database of systematic reviews, (4) .
Leventhal, T., & Brooks-Gunn, J. (2000). The neighborhoods they live in: the effects of neighborhood residence on child and adolescent outcomes . Psychological Bulletin, 126 (2), 309.
Lippard, C. N., La Paro, K. M., Rouse, H. L., & Crosby, D. A. (2018, February). A closer look at teacher–child relationships and classroom emotional context in preschool . In Child & Youth Care Forum 47 (1), 1-21.
Navarro, J. L., & Tudge, J. R. (2022). Technologizing Bronfenbrenner: neo-ecological theory. Current Psychology , 1-17.
Paat, Y. F. (2013). Working with immigrant children and their families: An application of Bronfenbrenner’s ecological systems theory . Journal of Human Behavior in the Social Environment, 23 (8), 954-966.
Rosa, E. M., & Tudge, J. (2013). Urie Bronfenbrenner’s theory of human development: Its evolution from ecology to bioecology. Journal of family theory & review , 5 (4), 243-258.
Rhodes, S. (2013). Bronfenbrenner’s Ecological Theory [PDF]. Retrieved from http://uoit.blackboard.com
Tudge, J. R., Mokrova, I., Hatfield, B. E., & Karnik, R. B. (2009). Uses and misuses of Bronfenbrenner’s bioecological theory of human development. Journal of family theory & review , 1 (4), 198-210.
Wilson, P., Atkinson, M., Hornby, G., Thompson, M., Cooper, M., Hooper, C. M., & Southall, A. (2002). Young minds in our schools-a guide for teachers and others working in schools . Year: YoungMinds (Jan 2004).
Bronfenbrenner, U. (1974). Developmental research, public policy, and the ecology of childhood. Child Development, 45.
Harvard Business School Online's Business Insights Blog provides the career insights you need to achieve your goals and gain confidence in your business skills.
Becoming a more data-driven decision-maker can bring several benefits to your organization, enabling you to identify new opportunities to pursue and threats to abate. Rather than allowing subjective thinking to guide your business strategy, backing your decisions with data can empower your company to become more innovative and, ultimately, profitable.
If you’re new to data-driven decision-making, you might be wondering how data translates into business strategy. The answer lies in generating a hypothesis and verifying or rejecting it based on what various forms of data tell you.
Below is a look at hypothesis testing and the role it plays in helping businesses become more data-driven.
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To understand what hypothesis testing is, it’s important first to understand what a hypothesis is.
A hypothesis or hypothesis statement seeks to explain why something has happened, or what might happen, under certain conditions. It can also be used to understand how different variables relate to each other. Hypotheses are often written as if-then statements; for example, “If this happens, then this will happen.”
Hypothesis testing , then, is a statistical means of testing an assumption stated in a hypothesis. While the specific methodology leveraged depends on the nature of the hypothesis and data available, hypothesis testing typically uses sample data to extrapolate insights about a larger population.
When it comes to data-driven decision-making, there’s a certain amount of risk that can mislead a professional. This could be due to flawed thinking or observations, incomplete or inaccurate data , or the presence of unknown variables. The danger in this is that, if major strategic decisions are made based on flawed insights, it can lead to wasted resources, missed opportunities, and catastrophic outcomes.
The real value of hypothesis testing in business is that it allows professionals to test their theories and assumptions before putting them into action. This essentially allows an organization to verify its analysis is correct before committing resources to implement a broader strategy.
As one example, consider a company that wishes to launch a new marketing campaign to revitalize sales during a slow period. Doing so could be an incredibly expensive endeavor, depending on the campaign’s size and complexity. The company, therefore, may wish to test the campaign on a smaller scale to understand how it will perform.
In this example, the hypothesis that’s being tested would fall along the lines of: “If the company launches a new marketing campaign, then it will translate into an increase in sales.” It may even be possible to quantify how much of a lift in sales the company expects to see from the effort. Pending the results of the pilot campaign, the business would then know whether it makes sense to roll it out more broadly.
Related: 9 Fundamental Data Science Skills for Business Professionals
1. alternative hypothesis and null hypothesis.
In hypothesis testing, the hypothesis that’s being tested is known as the alternative hypothesis . Often, it’s expressed as a correlation or statistical relationship between variables. The null hypothesis , on the other hand, is a statement that’s meant to show there’s no statistical relationship between the variables being tested. It’s typically the exact opposite of whatever is stated in the alternative hypothesis.
For example, consider a company’s leadership team that historically and reliably sees $12 million in monthly revenue. They want to understand if reducing the price of their services will attract more customers and, in turn, increase revenue.
In this case, the alternative hypothesis may take the form of a statement such as: “If we reduce the price of our flagship service by five percent, then we’ll see an increase in sales and realize revenues greater than $12 million in the next month.”
The null hypothesis, on the other hand, would indicate that revenues wouldn’t increase from the base of $12 million, or might even decrease.
Check out the video below about the difference between an alternative and a null hypothesis, and subscribe to our YouTube channel for more explainer content.
Statistically speaking, if you were to run the same scenario 100 times, you’d likely receive somewhat different results each time. If you were to plot these results in a distribution plot, you’d see the most likely outcome is at the tallest point in the graph, with less likely outcomes falling to the right and left of that point.
With this in mind, imagine you’ve completed your hypothesis test and have your results, which indicate there may be a correlation between the variables you were testing. To understand your results' significance, you’ll need to identify a p-value for the test, which helps note how confident you are in the test results.
In statistics, the p-value depicts the probability that, assuming the null hypothesis is correct, you might still observe results that are at least as extreme as the results of your hypothesis test. The smaller the p-value, the more likely the alternative hypothesis is correct, and the greater the significance of your results.
When it’s time to test your hypothesis, it’s important to leverage the correct testing method. The two most common hypothesis testing methods are one-sided and two-sided tests , or one-tailed and two-tailed tests, respectively.
Typically, you’d leverage a one-sided test when you have a strong conviction about the direction of change you expect to see due to your hypothesis test. You’d leverage a two-sided test when you’re less confident in the direction of change.
To perform hypothesis testing in the first place, you need to collect a sample of data to be analyzed. Depending on the question you’re seeking to answer or investigate, you might collect samples through surveys, observational studies, or experiments.
A survey involves asking a series of questions to a random population sample and recording self-reported responses.
Observational studies involve a researcher observing a sample population and collecting data as it occurs naturally, without intervention.
Finally, an experiment involves dividing a sample into multiple groups, one of which acts as the control group. For each non-control group, the variable being studied is manipulated to determine how the data collected differs from that of the control group.
Hypothesis testing is a complex process involving different moving pieces that can allow an organization to effectively leverage its data and inform strategic decisions.
If you’re interested in better understanding hypothesis testing and the role it can play within your organization, one option is to complete a course that focuses on the process. Doing so can lay the statistical and analytical foundation you need to succeed.
Do you want to learn more about hypothesis testing? Explore Business Analytics —one of our online business essentials courses —and download our Beginner’s Guide to Data & Analytics .
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The U.S. Department of the Treasury’s Community Development Financial Institutions Fund (CDFI Fund) released a revised Community Development Financial Institution (CDFI) Certification Application Frequently Asked Questions (FAQs) document, Pre-Approved Target Market Assessment Methodology guidance, and an adjusted CDFI Certification Application timeline today.
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Xiaoyue zhu, chao qian, erping li, and hongsheng chen, phys. rev. lett. 133 , 113801 – published 9 september 2024.
The past decades have witnessed the rapid development of metamaterials and metasurfaces. However, loss is still a challenging problem limiting numerous practical applications, including long-range wireless communications, superscattering, and non-Hermitian physics. Recently, great effort has been made to minimize the loss, however, they are too complicated for practical implementation and still restricted by the theoretical limit. Here, we propose and experimentally realize a tunable gain metasurface induced by negative conductivity, with deep theoretical analysis from scattering theory and equivalent circuits. In the experiment, we create metasurface samples embedded with tunable negative (or positive) conductivity to achieve adjustable gain (or loss). By varying the control bias voltages, the metasurfaces can reflect incident waves with additional controllable gain. Interestingly, we find the gain metasurfaces inherently pose nonlinearities, which are beneficial for nonlinear optics and microwave applications, particularly for the nonlinear activation of wave-based neural networks.
DOI: https://doi.org/10.1103/PhysRevLett.133.113801
© 2024 American Physical Society
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Vol. 133, Iss. 11 — 13 September 2024
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Conceptual illustration of gain metasurfaces. When the incident wave impinges on the metasurface, it is reflected with an additional gain that can be modulated by adjusting the bias voltages ( V 1 − V 4 ). The coordinate is settled at the center of metasurfaces. The diagram at the center bottom represents the operational states of the metamaterials. Typically, metasurfaces used to work in a lossy state represented by the purple region where magnitudes of reflection coefficients ( Γ ) are less than 1. The bottom left corner of the figure elucidates the underlying microscopic mechanisms, where conductivity [ σ ( ω ) ] and imaginary components of the effective permittivity [ ε eff ″ ( ω ) ] are positive. In contrast, ours operate in gain states denoted by the orange region where magnitudes of Γ exceed 1. To achieve this, ε eff ″ ( ω ) and σ ( ω ) should be negative, which also leads to changes in currents as illustrated by J ¯ 2 and J ¯ 1 . S ¯ in and S ¯ out refer to Poynting vectors of incident and reflected waves. And S ¯ ′ indicates the Poynting vector of additional power flow provided by the gain metasurfaces where Re [ ∇ · S ¯ ] > 0 .
Design of gain metasurfaces. (a) Three-dimensional illustration of the gain metasurface. The unit cell structure can be characterized by the structural parameters: a 1 = 50 , b 1 = 60 , h = 1 , w 2 = 10 , w 1 = 19 , p 1 = 48 , p 2 = 20 , g 1 = 2 (units: mm). The overall 3D size is a 1 · b 1 · h 1 . TD indicates the tunnel diode. The symbols Z 21 , Z 22 , Z 23 denote equivalent impedances of these three metallic patch parts, respectively. (b) Equivalent circuit models. Both Γ L and Z L represent reflection coefficients and the equivalent terminal impedance observed from the reflection wave ports, respectively. − R d can be continuously manipulated in positive or negative regions. (c) Current-voltage ( I − V ) curves. Tested currents with voltages directly varying. The differential resistance values R 1 , R 2 , R 3 , and R 4 are about − 42 Ω , − 17.5 Ω , 0 Ω , and 48 Ω , respectively. (d) Simulated spectra of reflection coefficients with the differential resistances of TD being R 1 ∼ R 4 .
Experimental results. (a) A photograph of experimental setups. T and R represent the transmitter and receiver, respectively. The H -shaped gain metasurfaces can work in a a wide range of incident angle. (b) Gain—voltage curves. Measured gains of the two samples are plotted correspondingly with the total bias voltage changing. The two kinds of samples are designed to work in different bands. More details can be found in Supplemental Material [ 33 ], notes 2 and 3. (c),(d) The gain evolution processes of samples 1 and 2 with total bias voltage changing.
Natural nonlinearity and potential applications in wave-based neural networks. (a) An illustration of wave-based neural network structure, which encompasses matrix multiplication and nonlinear activation. The waves that propagate from one layer to the next carry varying phase and magnitude information, acting as trainable weights between adjacent network layers. Herein, X 1 − X 4 , Y 1 − Y 4 , b , and f are inputs, outputs, bias, and activation, respectively. (b) With the input power linearly enlarging, the output power can increase nonlinearly.
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A theory is broad in nature and explains larger bodies of data. A hypothesis is more specific and makes a prediction about the outcome of a particular study. Working with theories is not "icing on the cake." It is a basic ingredient of psychological research. Like other scientists, psychologists use the hypothetico-deductive method.
Research Hypothesis: Definition, Types, Examples and ...
Research Hypothesis: What It Is, Types How to Develop?
Definition: Hypothesis is an educated guess or proposed explanation for a phenomenon, based on some initial observations or data. It is a tentative statement that can be tested and potentially proven or disproven through further investigation and experimentation. Hypothesis is often used in scientific research to guide the design of experiments ...
What is a research hypothesis: How to write it, types, and ...
Essentially, a hypothesis is a tentative statement that predicts the relationship between two or more variables in a research study. It is usually derived from a theoretical framework or previous ...
Hypothesis: Definition, Examples, and Types
"A hypothesis is a conjectural statement of the relation between two or more variables". (Kerlinger, 1956) "Hypothesis is a formal statement that presents the expected relationship between an independent and dependent variable."(Creswell, 1994) "A research question is essentially a hypothesis asked in the form of a question."
The research hypothesis is needed for a sound and well-developed research study. The research hypothesis contributes to the solution of the research problem. Types of research hypotheses include inductive and deductive, directional and non-directional, and null and alternative hypotheses. Rejecting the null hypothesis and accepting the ...
It is important to understand that research is a process. Theory development and evaluation take time. A single test of a theory provides evidence, but rarely (if ever) conclusive evidence. A theory and an associated hypothesis can predict a specific outcome, and if the predicted outcome is obtained it provides support for the theory.
Hypothesis generation is an early and critical step in any hypothesis-driven clinical research project. Because it is not yet a well-understood cognitive process, the need to improve the process goes unrecognized. Without an impactful hypothesis, the significance of any research project can be questionable, regardless of the rigor or diligence applied in other steps of the study, e.g., study ...
4. Formulate your hypothesis. After collecting background information and making a prediction based on your question, plan a statement that lays out your variables, subjects and predicted outcome. Whether you write it as an "if/then" or declarative statement, your hypothesis should include the prediction to be tested.
Developmental theories: Past, present, and future
Chapter 6 Overview. This chapter discusses the third step of the SGAM, highlighted below in gold, Hypothesis Development. A hypothesis is often defined as an educated guess because it is informed by what you already know about a topic. This step in the process is to identify all hypotheses that merit detailed examination, keeping in mind that ...
Hypothesis needs to be structured before the data-gathering and interpretation phase of the research. A well-grounded hypothesis indicates that the researcher has sufficient knowledge in the area to undertake the investigation. The hypothesis gives direction to the collection and interpretation of data.
Applications of Hypothesis Testing in Research. Hypothesis testing isn't only confined to numbers and calculations; it also has several real-life applications in business, manufacturing, advertising, and medicine. ... During ideation and strategy development, C-level executives use hypothesis testing to evaluate their theories and assumptions ...
The application of nursing theory in nursing practice standards is a fundamental aspect that enriches and informs the delivery of high-quality patient care. Nursing theories provide a theoretical framework that guides the development and refinement of practice standards, ensuring that they align with the profession's core values and principles.
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The steps of the scientific method are to: Make observations. Formulate a hypothesis. Design an experiment to test the hypothesis. State the indicators to evaluate if the experiment has succeeded. Conduct the experiment. Evaluate the results of the experiment. Accept or reject the hypothesis.
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A series of research methods based on FDFT continues to emerge. In this perspective, the development history and applications in various fields of FDFT are summarized, including time-dependent FDFT, reaction-coupled FDFT, and quantum density functional theory combined FDFT (i.e. joint density functional theory).
City residents, builders and the development industry may now submit and pay for all Building Code Services permits and applications from the comfort of their home, office or work site using any mobile device. The new Building, Planning and Land Development online customer portal is available through My Service Ottawa. Building Code Services online applications and permits introduces a new ...
A graduate of the Keystone program will have the theory and the practical experience to excel in their chosen career field. Keystone alumni are also eligible for DCMA leadership training, like the Emerging Leaders program, said Bowers.
Activity: Summary Table of Piaget's Theory of Cognitive Development; Activity: Apply it - Schemas at The Zoo ... Application, Evaluation Questions; Plenary: Consolidation Question; To request lessons, provide feedback or if you have had any issues opening any resources of my resources, please feel free to contact [email protected].
The U.S. Department of the Treasury's Community Development Financial Institutions Fund (CDFI Fund) released a revised Community Development Financial Institution (CDFI) Certification Application Frequently Asked Questions (FAQs) document, Pre-Approved Target Market Assessment Methodology guidance, and an adjusted CDFI Certification Application timeline today.
The highly acclaimed Practical Application of Toxicology in Drug Development (PATDD) course co-organised by Cambridge Academy of Therapeutic Sciences (CATS) and The British Toxicology Society (BTS) provides comprehensive training in toxicology as applied to drug development, catering to scientists from around the globe. Participants will gain a thorough understanding of non-clinical safety ...
The past decades have witnessed the rapid development of metamaterials and metasurfaces. However, loss is still a challenging problem limiting numerous practical applications, including long-range wireless communications, superscattering, and non-Hermitian physics. Recently, great effort has been made to minimize the loss, however, they are too complicated for practical implementation and ...