Methods in Psychology

‭Building Body of Research‬

‭Putting it All Together‬
‭➔‬ ‭scientific literature: series of related studies, by various researchers, conducted on the same‬
‭topic‬
‭◆‬ ‭aka ‘‬‭body of research‬‭’‬
‭➔‬ ‭theory testing and replication provide foundation for building a body of research on a topic‬
‭➔‬ ‭theory building vs theory testing‬
‭◆‬ ‭theory building = observation → data collection → pattern →‬‭theory‬
‭◆‬ ‭theory testing (hypothesis testing) =‬‭theory‬‭→ hypothesis‬‭→ data collection → theory‬
‭testing‬


‭Replication Is Key‬
‭➔‬ ‭direct replication‬‭: conducting the exact same study‬
‭◆‬ ‭using a sample from the‬‭same‬‭population‬
‭◆‬ ‭using the‬‭same‬‭methods‬
‭◆‬ ‭establishes‬‭statistical validity‬
‭◆‬ ‭goal is to control for type 1 error‬
‭➔‬ ‭conceptual replication (across diff populations)‬‭:‬‭re-testing the same theoretical‬
‭idea/hypothesis using a‬‭different population‬
‭◆‬ ‭establishes‬‭external validity‬
‭●‬ ‭seeing whether the same pattern of results generalize to other populations‬
‭➔‬ ‭conceptual replication (across diff variable operationalizations)‬‭:‬‭re-testing the same‬
‭theoretical idea/hypothesis using‬‭different operationalizations‬‭of the‬‭same constructs‬
‭◆‬ ‭establishes‬‭construct validity‬
‭●‬ ‭seeing if the same pattern of results occur even when a construct is measured‬
‭or manipulated in a diff way‬
‭➔‬ ‭pattern and parsimony‬‭: internal validity is strengthened‬‭when patterns of causality can be‬
‭established across multiple experimental studies‬
‭➔‬ ‭goals of replication can be combined and established in a single study‬


‭Summarizing Body of Research‬
‭➔‬ ‭review article‬‭:‬‭summarizes the key trends‬‭that emerge‬‭from the scientific literature‬
‭◆‬ ‭variety of kinds with diff focuses (i.e. some focus on the research, some focus on the‬
‭methods)‬
‭◆‬ ‭a more qualitative form of analysis‬
‭➔‬ ‭meta-analysis‬‭: averaging the statistical results of‬‭multiple studies to‬‭examine the overall‬
‭effect size‬
‭◆‬ ‭a more quantitative form of analysis‬

, ‭Conducting a Literature Review‬
‭➔‬ ‭the steps‬
‭◆‬ ‭formulate question‬
‭◆‬ ‭identify criterion‬
‭◆‬ ‭kew word search‬
‭◆‬ ‭scan abstracts (prescreening the articles)‬
‭◆‬ ‭choose articles‬
‭◆‬ ‭extract patterns‬
‭◆‬ ‭organize info‬
‭◆‬ ‭write paper on present results‬
‭➔‬ ‭flows similar to a regular study‬


‭Conducting A Meta-Analysis‬
‭➔‬ ‭the steps‬
‭◆‬ ‭formulate a question‬
‭◆‬ ‭identify criterion‬
‭◆‬ ‭key word search‬
‭◆‬ ‭scan abstracts‬
‭◆‬ ‭choose articles‬
‭◆‬ ‭extract effects‬
‭◆‬ ‭run analyses‬
‭◆‬ ‭report results‬


‭Publication Bias‬
‭➔‬ ‭null findings are less likely to be published‬
‭◆‬ ‭“the file drawer” problem‬
‭◆‬ ‭focusing on only published work could pose a issue with bias for conducting a review‬
‭or a meta-analysis‬
‭➔‬ ‭solution: including both published and unpublished studies‬


‭Interpreting Forest Plots‬
‭➔‬ ‭meta-analyses average the effect size for each study in order to calculate the overall effect‬
‭size‬
‭➔‬ ‭sometimes diff studies give diff weights in calculations based on sample size, quality of the‬
‭design, etc‬
‭◆‬ ‭accounted for in the plot’s size‬
‭●‬ ‭smaller plot = lower weight‬
‭●‬ ‭bigger plot = higher weight‬
‭➔‬ ‭the distribution of effect size can be compared to a line of ‘no effect’‬
‭◆‬ ‭the line defines the null hypothesis‬