Q: A researcher collects the following data set: 2, 4, 4, 6, 8. What is the mean of this data set? Use the formula $$\text{Mean} = \frac{\sum x}{N}.$$

$$\text{Mean} = \frac{2+4+4+6+8}{5} = \frac{24}{5} = 4.8$$

Question 1

Which of the following best describes the primary purpose of descriptive statistics in research?

Accepted Answer

To describe and summarize data collected in a study

Question 2

A researcher collects the following data set: 2, 4, 4, 6, 8. What is the mean of this data set? Use the formula $$	ext{Mean} = \frac{\sum x}{N}.$$

Accepted Answer

$$	ext{Mean} = \frac{2+4+4+6+8}{5} = \frac{24}{5} = 4.8$$

Question 3

Which measure of central tendency is most appropriate for categorical data?

Accepted Answer

Mode

Question 4

A data set contains the following values: 1, 2, 2, 3, 4, 7, 9. What is the median? (Recall: Median is the middle value when data are ordered.)

Accepted Answer

3

Question 5

Which of the following is a limitation of using the mean as a measure of central tendency?

Accepted Answer

It is affected by outliers and extreme values

Question 6

Given the data set: 3, 5, 7, 7, 8, 10, 12, what is the range? (Use $$	ext{Range} = 	ext{Max} - 	ext{Min}.)$$

Accepted Answer

$$	ext{Range} = 12 - 3 = 9$$

Question 7

Which of the following best describes the interquartile range (IQR)?

Accepted Answer

The difference between the 75th percentile (Q3) and the 25th percentile (Q1)

Question 8

A psychologist is analyzing test scores and wants to know how much the scores deviate from the mean. Which measure should she use?

Accepted Answer

Standard deviation

Question 9

Given the data set: 2, 4, 4, 4, 5, 7, 9, what is the mode?

Accepted Answer

4

Question 10

Which of the following is NOT a measure of variability?

Accepted Answer

Median

Question 11

A researcher wants to graphically display the mean scores of three groups. Which type of graph is most appropriate?

Accepted Answer

Bar chart

Question 12

Which of the following steps is NOT part of calculating the standard deviation for a sample?

Accepted Answer

Multiply each score by the sample size

Question 13

In SPSS, which menu path would you use to calculate descriptive statistics for a variable?

Accepted Answer

Analyze \u003e Descriptive Statistics \u003e Descriptives

Question 14

A data set has the following values: 1, 2, 3, 4, 100. Which measure of central tendency would best represent the typical value in this data set?

Accepted Answer

Median

Question 15

Which of the following statements about the standard deviation is TRUE?

Accepted Answer

It measures the average amount by which scores deviate from the mean

Question 16

If a data set is perfectly symmetrical and unimodal, which of the following is TRUE?

Accepted Answer

Mean, median, and mode are all equal

Question 17

Which of the following is a correct formula for the sample standard deviation $$s$$?

Accepted Answer

$$s = \sqrt{\frac{\sum (x_i - \bar{x})^2$}{n-1}}$$

Question 18

A researcher is interested in the spread of the middle 50% of scores in a data set. Which measure should she use?

Accepted Answer

Interquartile range

Question 19

Which of the following is NOT a step in preparing your data for analysis in SPSS?

Accepted Answer

Analyzing the data before cleaning

Question 20

A health researcher wants to compare the coping scores of three groups using SPSS. Which sequence of actions will allow her to graph the mean scores for each group?

Accepted Answer

Graphs \u003e Chart Builder \u003e Bar \u003e Simple \u003e Assign variables \u003e OK

Descriptive Statistics and Introduction to SPSS: Study Notes for Health Sciences

Study Guide - Practice Questions

Study Guide - Flashcards