Question 1

Which of the following best describes the main purpose of linear regression in statistical analysis?

Accepted Answer

To predict the value of a dependent variable based on one independent variable

Question 2

A researcher wants to examine whether there is a significant difference in blood pressure before and after a new medication in the same group of patients. Which statistical test is most appropriate?

Accepted Answer

Dependent t-test

Question 3

Which of the following equations represents a multiple regression model?

Accepted Answer

$$y = a + b_1x_1 + b_2x_2 + \ldots + b_rx_r$$

Question 4

A hospital administrator wants to know if there is an association between gender (male/female) and whether patients develop diabetes (yes/no). Which statistical test should be used?

Accepted Answer

Chi-square test of independence

Question 5

Which of the following correlation coefficients indicates the strongest negative linear relationship between two variables?

Accepted Answer

$$r = -0.85$$

Question 6

A study compares the mean math scores of three different teaching methods among students. Which statistical test is most appropriate?

Accepted Answer

ANOVA

Question 7

Which of the following is a key assumption of Pearson’s correlation coefficient?

Accepted Answer

Both variables are measured at the interval or ratio level

Question 8

A researcher wants to test if there is a difference in the proportion of smokers before and after a public health campaign in the same group of individuals. Which test should be used?

Accepted Answer

McNemar test

Question 9

Which of the following best describes the dependent variable in logistic regression?

Accepted Answer

It is binary (e.g., success/failure)

Question 10

A researcher is interested in the relationship between the number of hours studied and exam scores, both measured on a continuous scale. Which statistical test is most appropriate?

Accepted Answer

Pearson correlation

Question 11

Which formula is used to calculate the test statistic for an independent t-test?

Accepted Answer

$$t = \frac{\bar{x}_1 - \bar{x}_2}{\sqrt{\frac{s_1$^2}{n_1$} + \frac{s_2$^2}{n_2$}}}$$

Question 12

Which statistical test would be most appropriate to compare the mean cholesterol levels of patients before and after a diet intervention in the same group?

Accepted Answer

Dependent t-test

Question 13

A researcher wants to examine the association between education level (ordinal) and income (ratio). Which correlation coefficient is most appropriate?

Accepted Answer

Spearman rho

Question 14

Which of the following is NOT a requirement for using ANOVA?

Accepted Answer

The dependent variable must be nominal

Question 15

In a regression analysis, which model would you select if you want the lowest standard error for your predictions?

Accepted Answer

The model with the best fit to the data

Question 16

Which of the following best describes the use of the chi-square test?

Accepted Answer

To test the association between two categorical variables

Question 17

A study measures the relationship between rank in a competition (1st, 2nd, 3rd, etc.) and satisfaction score (ordinal). Which correlation should be used?

Accepted Answer

Spearman rho

Question 18

Which of the following is the correct formula for the chi-square statistic?

Accepted Answer

$$\$$chi^2$$ = \sum \frac{(O - E)^2$}{E}$$

Question 19

A researcher wants to compare the mean test scores of students from three different schools. Which statistical test should be used?

Accepted Answer

ANOVA

Question 20

Which of the following scenarios would require the use of a repeated measures ANOVA?

Accepted Answer

Measuring the same group of patients’ blood pressure at three different time points

Statistical Tests, Regression, and Correlation: Study Guide

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