Chapter 14 Test Items

1. In her recent research study, Christina reported a summary of the information/data about the participants. Which type of statistics did Christina use to provide this information?

a. inferential statistics

b. descriptive statistics

c. quantitative statistics

d. qualitative statistics

2. Which of the following is NOT a benefit of statistics?

a. Statistics allow us to summarize or describe data.

b. Statistics enable us to organization information in a meaningful way to make predictions.

c. Statistics assist us in understanding the world around us.

d. Statistics allow us to prove theories.

3. What is the mean for the following set of numbers?

100 87 36 35 29

a. 57.40

b. 33.38

c. –2.79

d. .66

4. What is the kurtosis for the following set of numbers?

100 87 36 35 29

a. -2.79

b. 33.38

c. 57.40

d. .66

5. How would you characterize the skewness of the following set of numbers?

100 87 36 35 29

a. positively skewed

b. negatively skewed

c. peaked

d. flat

6. How would you characterize the kurtosis of the following set of numbers?

100 87 36 35 29

a. peaked

b. negatively skewed

c. positively skewed

d. flat

7. Which of the following is true about the following set of numbers?

100 100 90 46 25 29 13 13

a. data are bimodal

b. mean is 75.32

c. data are negatively skewed

d. data are peaked

8. Which of the following is NOT an example of a descriptive statistic?

a. grade point average

b. number of years in school

c. results from the PRCA-24

d. gender

9. When data are analyzed in order to make inferences from a smaller group of data to a larger group of data we use which type of statistic?

a. inferential statistic

b. descriptive statistic

c. quantitative statistic

d. qualitative statistic

10. When data are analyzed in order to make inferences from a smaller group of data to a larger group of data, the larger group of data is referred to as the

a. sample

b. pool of participants

c. population

d. data pool

11. Which of the following measures how wide or spread out a distribution is?

a. mean

b. median

c. mode

d. variance

12. Which type of statistic is the standard deviation?

a. inferential statistic

b. descriptive statistic

c. quantitative statistic

d. qualitative statistic

13. Raekwon is in the process of running some basic descriptive statistics. He receives information that his kurtosis is –.57 and his skewness is .80. Based on this information, what can Raekwon say about his sample?

a. The sample is tall and not skewed.

b. The sample is flat and positively skewed.

c. The sample is tall and positively skewed.

d. The sample is flat and negatively skewed.

14. What is the median for the following set of numbers?

100 87 36 35 29

a. 57.40

b. 33.38

c. –2.79

d. 36

15. Which of the following is true about the following set of numbers?

100 100 90 46 46 29 13 13

a. data are bimodal

b. mean is 75.32

c. data are multimodal

d. data are peaked

16. For the following set of numbers, what is the mean (mean = ΣX/N)?

9 – 2 – 8 – 1 – 5

a. 5

b. 25

c. 8

d. 23

17. In Janell’s study, she finds the sum of squares for her variable is 20. She also has five participants in her study. What is her variance (s² = SS/ (N – 1.)?

a. 20

b. 5

c. 4

d. 1

18. To create a _______________, simply record the number of occurrences for each value in the dataset.

a. frequency distribution

b. inferential statistic

c. measure of central tendency

d. sample statistic

19. In his study Joey receives a kurtosis of .87. Which of the following is an accurate statement based on Joey’s kurtosis?

a. the sample is left (negatively) skewed

b. the sample is right (positively) skewed

c. the sample has a tall peak

d. the sample has a flat peak

20. In his study Joey receives a skewness of .54. Which of the following is an accurate statement based on Joey’s kurtosis?

a. the sample is left (negatively) skewed

b. the sample is right (positively) skewed

c. the sample has a tall peak

d. the sample has a flat peak

21. Kurtosis lets a researcher know whether or not her or his data are flat or peaked.

a. True

b. False

22. Inferential statistical tests allow researchers to make inferences about some unknown aspect of a sample from a population.

a. True

b. False

23. Mean, median, and mode are all examples of measures of variance.

a. True

b. False

24. If a data set has two modes, it is said to be bimodal.

a. True

b. False

25. If you find that your standard deviation is 9, then our variance would be 3.

a. True

b. False

26. A sample is used to best represent a portion of the population.

a. True

b. False

27. Mode is defined as the middle value in a list of data.

a. True

b. False

28. Median is defined as the value that appears most frequently in a list of data.

a. True

b. False

Essays:

29. Explain the benefits of using statistics.

30. What are measures of variability?

31. Explain the purpose of skewness and kurtosis.

32. Distinguish between descriptive and inferential statistics.

33. What variables are usually analyzed using descriptive statistics? In what section of a research study might audiences find descriptive statics reported?

Matching:

34. Match each of the following terms with the correct statement.

a. Standard Deviation = Square root of the variance.

b. Inferential = Statistics that are used to make predictions.

c. Population Mean = ΣX / N

d. Variance = Measures how wide or spread out a distribution is or the average distance of the scores for an interval or ration scale from the mean in squared units.

e. Data = Any record or observation.