Some questions in Part A require that youaccess data from *Statistics for People Who (Think**T**hey) Hate Statistics**. *This data is available on the student website underthe Student Test Resources link.

1. By hand, compute themean, median, and mode for the following set of 40 reading scores:

**SUMMARY**

31

32

43

42

24

34

25

44

23

43

24

36

25

41

23

28

14

21

24

17

25

23

44

21

13

26

23

32

12

26

14

42

14

31

52

12

23

42

32

34

2. Compute the means for thefollowing set of scores saved as Ch. 2 Data Set 3 using IBM®SPSS® software. Print out a copy of the output.

Hospital size (number ofbeds)

Infection rate (per 1,000admissions)

234

1.7

214

2.4

165

3.1

436

5.6

432

4.9

342

5.3

276

5.6

187

1.2

512

3.3

553

4.1

3. You are the manager of afast food store. Part of your job is to report which special is selling best tothe boss at the end of each day. Use your knowledge of descriptive statisticsand write one paragraph to let the boss know what happened today. Use thefollowing data. Do not use IBM®SPSS®software to compute the statistics needed; rather, doit by hand. Include a copy of your work.

Special number

Sold

Cost

Huge Burger

20

$2.95

Baby Burger

18

$1.49

Chicken Littles

25

$3.50

Porker Burger

19

$2.95

Yummy Burger

17

$1.99

Coney Dog

20

$1.99

Total specials sold

119

4. Suppose you are workingwith a data set that has some different (much larger or much smaller than therest of the data) scores. What measure of central tendency would you use andwhy?

5. For the following set ofscores, compute the range, the unbiased and the biased standard deviations, andthe variance. Do the exercise by hand.

31, 42, 35, 55, 54, 34, 25, 44, 35

Why is the unbiasedestimate greater than the biased estimate?

6. Use IBM®SPSS®software to compute all thedescriptive statistics for the following set of three test scores over thecourse of a semester. Which test had the highest average score? Which test hadthe smallest amount of variability?

Test 1

Test 2

Test 3

50

50

49

48

49

47

51

51

51

46

46

55

49

48

55

48

53

45

49

49

47

49

52

45

50

48

46

50

55

53

7. This practice problem usesthe data contained in the file named Ch. 3 Data Set 3. There are two variablesin this data set.

Variable

Definition

Height

Height in inches

Weight

Weight in pounds

Using IBM®SPSS®software, compute all of themeasures of variability you can for height and weight.

8. Review the followingfrequency distribution. Create a histogram either by hand or by using someother application such as a Microsoft®Excel®document.

Class interval

Frequency

90–100

12

80–89

14

70–79

20

60–69

24

50–59

28

40–49

29

30–39

21

20–29

15

10–19

17

0–9

12

9. A third-grade teacher islooking to improve her students’ level of engagement during group discussionsand instruction. She keeps track of each of the 15 third graders’ number ofresponses every day for 1 week. This information is available in Ch. 4 Data Set2. Use IBM®SPSS®software to create a bar chart (one bar for each day).

10. Identify whether thesedistributions are negatively skewed, positively skewed, or not skewed at all,and why.

a. This talented group ofathletes scored very high on the vertical jump task.

b. On this incredibly crummytest, everyone received the same score.

c. On the most difficultspelling test of the year, the third graders wept as the scores were delivered.

11. For each of the following,indicate whether you would use a pie, line, or bar chart, and why.

a. The proportion of freshmen,sophomores, juniors, and seniors in a particular university

b. Change in GPA over foursemesters

c. Number of applicants forfour different jobs

d. Reaction time to differentstimuli

e. Number of scores in each of10 categories

From Salkind (2011). Copyright © 2012 SAGE. All RightsReserved. Adapted with permission. Part B

**Complete** the questions below. Be specific and provideexamples when relevant.

**Cite** any sources consistent with APA guidelines.

Question

Answer

Salkind (2011) describes statistics as a “set of tools”(p. 18). How do behavioral scientists use those tools?

How would you use descriptive statistics to report theeffectiveness of a baseball team? How would you use inferential statistics toreport the effectiveness of a baseball team? In this example, what is thesample and what is the population?

What does a measure of central tendency tell us about adata set? Identify the three common measures of central tendency used indescriptive statistics and give an example of each. How do you calculatethem?

What is variability in a data set? Identify three measuresof variability used in descriptive statistics, explain how to calculate each,and give an example of each.