Advanced Research Methods and Experimental Design
Epistemology and Mixed Designs
Epistemological Frameworks
Advanced psychological research relies on robust epistemological frameworks. While traditional positivism dominated early experimental psychology, contemporary approaches often utilize pragmatism to justify mixed-methods designs. This allows researchers to integrate quantitative metrics with qualitative phenomenological insights, addressing complex behavioral phenomena more comprehensively.
Statistical Power
Always conduct an a priori power analysis to determine the necessary sample size. Underpowered studies inflate the risk of Type II errors and reduce the positive predictive value of statistically significant results.
Steps in Hierarchical Linear Modeling (HLM)
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1
Specify the Level-1 (individual) model.
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2
Specify the Level-2 (group/contextual) model.
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3
Estimate variance components (unconditional model) to calculate the Intraclass Correlation Coefficient (ICC).
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4
Introduce predictors at Level-1 and Level-2 to explain variance.
Which of the following best describes a Type II error in hypothesis testing?
A Type II error (false negative) occurs when a researcher fails to reject a null hypothesis that is actually false in the population.
Correct answer: Failing to reject a false null hypothesis
What term describes the extent to which research findings can be generalized to real-world settings?
Ecological validity refers to the realism of the experimental environment and the degree to which results apply to naturalistic, everyday contexts.
Correct answer: Ecological validity
Sources of Variance in ANOVA
| Variance Type | Description |
|---|---|
| Between-Groups | Variance due to the experimental manipulation or independent variable. |
| Within-Groups | Error variance due to individual differences and random noise. |