RA Statistical Analysis and Interpretation 2

Question 1

A chi-square test of independence is most appropriate when a researcher wants to:

Accepted Answer

Examine the relationship between two categorical variables

Answer

Compare means across three or more groups

Answer

Measure the strength of a linear relationship between two continuous variables

Answer

Determine if a single sample mean differs from a known population mean

Question 2

What is the primary purpose of a one-way ANOVA?

Accepted Answer

To compare means across three or more independent groups simultaneously

Answer

To compare the variances of two populations

Answer

To assess correlation between two continuous variables

Answer

To test whether a sample comes from a normal distribution

Question 3

A Pearson correlation coefficient of -0.85 between two variables indicates:

Accepted Answer

A strong negative linear relationship

Answer

A weak positive linear relationship

Answer

No meaningful relationship

Answer

A strong positive linear relationship

Question 4

What is the key difference between parametric and non-parametric statistical tests?

Accepted Answer

Parametric tests assume the data meets certain distribution assumptions; non-parametric tests do not

Answer

Parametric tests are always more accurate than non-parametric tests

Answer

Non-parametric tests can only be used with categorical data

Answer

Parametric tests are used only for small samples

Question 5

In research, statistical power refers to:

Accepted Answer

The probability of correctly detecting a true effect when one exists

Answer

The probability of making a Type I error

Answer

The sample size required to run a study

Answer

The magnitude of the observed effect

Question 6

In a research study, the null hypothesis typically states that:

Accepted Answer

There is no effect, difference, or relationship between variables

Answer

The researcher's predicted effect exists

Answer

The sample data is not representative of the population

Answer

The study design is flawed

Question 7

When should a paired (dependent) samples t-test be used instead of an independent samples t-test?

Accepted Answer

When the same participants are measured twice or are matched across conditions

Answer

When comparing more than two groups

Answer

When the data is not normally distributed

Answer

When the sample size is very large