Important Concepts

Question 1

What are the threats to internal validity in research?

Answer 1

• Maturation of subjects
• Mortality (subjects withdrawing)
• Instruments used to measure behavior
• Statistical regression

Internal validity assesses whether the dependent variables were influenced by the independent variables.

Question 2

Surveys typically have return rate of ____ to ____%
But you need at least ____% return rate to generalize results
Need a minimum of ____ completed surveys,

Answer 2

30 to 50% return rate
75% to generalize results
100 surveys

Question 4

What does Cohen’s d effect size (ES) statistic gauge?

Answer 4

• Small: 0.2
• Medium: 0.5
• Large: 0.8

It measures the strength of a relationship in research findings.