Replication, Generalization, and External Validity In the Discussion for this week, you addressed one of the threats to the internal validity of a study, that is, confounding variables. This Application Assignment will challenge you to consider possible threats to external validity. Generalization is the extent to which relations among variables in research studies can be demonstrated among a wide variety of people and across different settings. When the results of a research study are generalizable to additional populations and settings, the study demonstrates external validity . However, if a research study is only valid for the particular sample used in the study, then it is not very helpful to the study of psychology. In the example provided in the Discussion introduction, two online student groups used different study strategies. Now imagine a human resource (HR) manager at a corporation, struggling with the concept of reading comprehension among employees in the workplace setting, wanted to try the new study strategy that the online course instructor had researched. Assume that the online college course instructor had resolved possible issues relating to internal validity and found that the new study strategy was effective at improving reading comprehension. The HR manager presumes that the results of the study with online college students will generalize to her training course at work. However, the replication of the study revealed that, although the new strategy was found to work well for online students, the results did not generalize to the training course in the work setting. Therefore, the original study lacks external validity. Replications of studies, such as the one in this example, are essential to demonstrate generalization and external validity. This week, you will learn about four types of replication procedures, and you will develop original examples of each procedure with the goal of demonstrating generalization and external validity. To prepare: · Review Chapter 13 from the course text. The Assignment (1–2 pages): · Explain the four different types of replications and the purpose of each. Include for each type of replication a brief original psychological study example (i.e., make up your own) that is different for each type of replication (i.e., do not build on the same example). Plan to devote a short paragraph for each. · Briefly explain how replications relate to the concepts of generalization and external validity. Note: Support the responses within your assignment with evidence from the assigned Learning Resources. Provide a reference list for resources you used for this Assignment. Submit your Assignment by Day 7 . Raptures to use: Stangor, C. (2015). Research methods for the behavioral sciences (5th ed.). Stamford, CT: Cengage Learning. Chapter 12, “Experimental Control and Internal Validity†Chapter 13, “External Validity†Gender identity is the subjective experience of being male or female. For most people, gender identity matches their sex; usually, men "feel" like they are men, and women "feel" like they are women. However, there are individuals whose sex and gender identity do not match; these people are referred to as transgendered. For example, a person born male may strongly identify with the female gender, even in childhood. This individual may prefer female friends, may participate in traditionally feminine activities, and may wish to dress like a girl or woman. Transgendered people may elect to undergo hormone treatments and possibly surgery to alter their bodies to match their gender identity, thus becoming transsexuals. Others may not alter their biological sex, but dress and act in ways to match their gender identity. Sexual orientation among the transgendered is variable; for example, some transgendered/transsexual males may be attracted to other males, while others may prefer female sexual partners. In this Application Assignment, you will draw on two types of sources of information about the biological basis of gender identity: the textbook's coverage of the topic, which provides a broad but shallow survey of the research literature in this area, and a journal article on the topic, which will give you a more in-depth look at one specific research study. These two types of sources are often complementary - the first provides breadth of coverage but usually lacks specificity or detail, while the second provides depth but lacks perspective. You will need to reflect on how these two different types of sources, taken together, provide a more comprehensive picture of a topic than either one alone. To prepare for this assignment Review the textbook's coverage of the development of sexual characteristics, paying special attention to discussions of biological factors that contribute to behavioral and psychological differences between males and females, sexual anomalies (particularly pseudohermaphroditism), and sexual orientation. In the Walden Library's database of journals, locate and read at least one case study or research report of transgendered or transsexual individuals. Think about how the information in the journal article relates to information from the textbook. The assignment: (1–2 pages) Considering both "typical" and "atypical" (i.e., pseudohermaphrodites) sexual development, briefly analyze the effects sex hormones seem to have on the development of gender-related behavioral and psychological characteristics in humans. In other words, what "masculine" characteristics are related to male hormones, and what "feminine" characteristics are related to female hormones? Briefly summarize the journal article you found, including discussion of the following points, if relevant: At what age and in what ways the subject(s) demonstrated characteristics of transgender. Possible sources (causes) of these characteristics, if addressed in the article. Description and outcome of any treatments that were attempted, if addressed. Compare and contrast the two sources of information (textbook and journal article) regarding biology and gender identity. Include all of the following that are relevant: How do the sources differ with respect to the type of information provided? In other words, what information can be gained from a literature review (textbook) versus a case study/research report (journal article)? On what points do the two sources agree? On what points do the two sources disagree? How do the two sources complement one another in helping you to understand the biological basis of gender identity? Be specific, using examples where appropriate. Support your Application Assignment with specific references to all resources used in its preparation. You are asked to provide a reference list only for those resources not included in the Learning Resources for this course. Resources to use: Readings Course Text: Garrett, B. (2015). Brain and Behavior: An Introduction to Biological Psychology, (4th ed.). Los Angeles: Sage. Chapter 6, "Motivation and the Regulation of Internal States" (pp. 159–195) Chapter 7, "The Biology of Sex and Gender" (pp. 197–229) A case study or research report from the Walden Library that discusses transgendered or transsexual individuals. Web Site Hunger, Satiation, and the Regulation of Fat Reserves (Brain and Behavior, Figure 6.7)

Paper For Above instruction

Replication is crucial in scientific research as it tests the reliability and validity of findings across different contexts, populations, or procedures. There are four main types of replication: exact, systematic, conceptual, and open. Each serves a unique purpose in advancing scientific knowledge and ensuring external validity and generalization of results.

Exact Replication

Exact replication involves repeating a study precisely as it was originally conducted, maintaining the original procedures, measures, and sample characteristics. The purpose is to verify whether the original findings can be reliably reproduced under the same conditions. For example, a psychologist studying the effects of a cognitive-behavioral therapy technique on reducing anxiety might replicate his study with the same sample demographic, identical procedures, and assessments. By doing so, researchers can determine if the original results were due to the intervention itself or other extraneous factors, thus strengthening internal and external validity. Exact replications bolster the confidence in findings and are essential for confirming scientific claims.

Systematic Replication

Systematic replication tests the same hypothesis but modifies certain methodological aspects, such as changing the sample population, settings, or measurement tools while keeping the core experimental questions intact. For instance, a study examining the impact of mindfulness meditation on stress reduction could be systematically replicated by applying the same protocol to a different demographic group, such as middle-aged men instead of college students. The purpose of this approach is to determine whether the original findings generalize across different populations and conditions—thus contributing to external validity. Systematic replications help identify the boundary conditions of phenomena, clarifying in which contexts the original results hold true.

Conceptual Replication

Conceptual replication involves testing the same theoretical idea or construct but using different procedures, measures, or operationalizations. For example, if the original study assessed self-control using a delay of gratification task, a conceptual replication might evaluate self-control through questionnaire measures or behavioral tasks designed differently but aimed at assessing the same underlying construct. The primary purpose is to evaluate the robustness of the theoretical framework across various operationalizations. This type of replication provides a deeper understanding of the concepts and helps confirm whether the core theory is valid across different methodological approaches, enhancing the external validity of the theoretical model.

Open Replication

Open replication emphasizes transparency and reproducibility, often involving publishing the full detailed methodology and encouraging other researchers to conduct real-world replications openly. Unlike the other types, open replication may not aim to exactly duplicate the original but instead promotes collaboration and verification across different labs and contexts. An example could involve multiple research teams independently testing the same phenomenon—such as the effect of social exclusion on prosocial behavior—using their own methods but sharing full procedures and data openly. This approach fosters scientific integrity, reproducibility, and external validity by allowing multiple independent investigations into the same research question, thus broadening the evidence base and identifying potential moderator variables.

Relation to External Validity and Generalization

Repetitions through these four types of replication are essential in establishing the external validity and generalizability of psychological findings. Exact replications ensure that specific results are reliable and not due to chance or specific conditions, while systematic and conceptual replications test whether findings hold across different populations and operational definitions, thus supporting generalization. Open replications further bolster external validity by encouraging transparent, collaborative verification in diverse external contexts. Collectively, these replication types contribute to building a robust scientific knowledge base that accurately reflects psychological phenomena across varied settings and groups. Their importance cannot be overstated, as they provide the evidence needed to confirm whether initial findings are broadly applicable or context-dependent, thereby guiding theory development and practical applications in psychology.

References

• Stangor, C. (2015). Research methods for the behavioral sciences (5th ed.). Stamford, CT: Cengage Learning.
• Garrett, B. (2015). Brain and Behavior: An Introduction to Biological Psychology. Los Angeles: Sage.
• Open Science Collaboration. (2015). Estimating the reproducibility of psychological science. Science, 349(6251), aac4716. https://doi.org/10.1126/science.aac4716
• Simons, D. J., et al. (2016). The Open Science Collaboration's project: Replication and reproducibility in psychology. Perspectives on Psychological Science, 11(5), 607-612. https://doi.org/10.1177/1745691616652870
• Maxwell, S. E., & Cole, D. A. (2007). Bias in cross-sectional studies. Psychological Methods, 12(4), 247-267. https://doi.org/10.1037/1082-989X.12.4.247
• Earp, B. D., & Trafimow, D. (2015). Replication, reproducibility, and the scientific method. Frontiers in Psychology, 6, 764. https://doi.org/10.3389/fpsyg.2015.00764
• Ioannidis, J. P. (2005). Why most published research findings are false. PLOS Medicine, 2(8), e124. https://doi.org/10.1371/journal.pmed.0020124
• Chambless, D. L., & Hollon, S. D. (1998). Defining empirically supported therapies. Journal of Consulting and Clinical Psychology, 66(1), 7-18. https://doi.org/10.1037/0022-006X.66.1.7
• Niell, R., et al. (2016). Enhancing reproducibility in psychological science: Practical steps. Perspectives on Psychological Science, 11(5), 649-655. https://doi.org/10.1177/1745691616655594
• Open Science Framework. (2020). The OSF library of registered reports and replications. https://osf.io/