BAPSY - Bachelor of Arts in Psychology Bachelor of Arts in Psychology: Methodical & Stats Analysis 1

Question 1

A researcher sets alpha at 0.05 and fails to reject a null hypothesis that is actually false. What type of error has occurred?

Accepted Answer

Type II error

Answer

Type I error

Answer

Sampling error

Answer

Measurement error

Question 2

A multiple regression model yields R² = 0.64. A researcher adds a second predictor and R² increases to 0.65. What should the researcher most likely conclude?

Accepted Answer

The increase in R² is likely due to chance and the predictor adds little value

Answer

The second predictor significantly improves the model

Answer

The model now explains 65% less variance

Answer

Multicollinearity has been eliminated

Question 3

Cohen's d is calculated as 0.20 for a study comparing two group means. How is this effect size conventionally interpreted?

Accepted Answer

Small effect

Answer

Large effect

Answer

Medium effect

Answer

No effect

Question 4

A psychologist measures anxiety levels in the same group of participants before therapy, after 4 weeks, and after 8 weeks. Which statistical test is most appropriate?

Accepted Answer

Repeated-measures ANOVA

Answer

Independent-samples t-test

Answer

One-way between-subjects ANOVA

Answer

Chi-square goodness-of-fit test

Question 5

A scale measuring depression produces very similar scores when administered to the same participants two weeks apart. This scale demonstrates high:

Accepted Answer

Test-retest reliability

Answer

Content validity

Answer

Construct validity

Answer

Criterion validity

Question 6

In a normal distribution, approximately what percentage of scores fall within one standard deviation above and below the mean?

Accepted Answer

68%

Answer

50%

Answer

95%

Answer

99.7%