CRS Statistical Analysis & Software 2

Question 1

In SPSS, which procedure is used to test whether the means of three or more independent groups differ significantly?

Accepted Answer

One-Way ANOVA

Answer

One-Way ANOVA (Analyze > Compare Means > One-Way ANOVA) tests for significant mean differences across three or more independent groups.

Question 2

What does a Cronbach's alpha value of 0.85 indicate about a research scale?

Accepted Answer

The scale has high internal consistency

Answer

A Cronbach's alpha of 0.85 indicates high internal consistency, meaning items on the scale are strongly correlated with each other.

Question 3

When conducting a chi-square test of independence, what is the minimum expected cell frequency recommended to ensure test validity?

Accepted Answer

5

Answer

The standard rule requires expected cell frequencies of at least 5 in each cell to ensure the chi-square approximation is valid.

Question 4

In R, which function is used to create a linear regression model?

Accepted Answer

lm()

Answer

The lm() function in R fits linear models, returning coefficients, residuals, and model fit statistics.

Question 5

What statistical concept does the term 'heteroscedasticity' refer to in regression analysis?

Accepted Answer

Non-constant variance of residuals across fitted values

Answer

Heteroscedasticity occurs when the variance of regression residuals is not constant across all levels of the independent variable.

(CRS) Certified Research Specialist Practice Test