Psychology and Statistics

Psychologyand Statistics

Answersto Chapter Seven Review Exercise

1.Frequency distribution table 2. Qualitative variable

3.Histogram 4 .Central tendency

5.Median 6. Standard deviation

7.Sample mean 8. Population, sample

9.Standard score 10. Standard normal distribution.

11.Pearson 12. Point-biserial

13.Coefficient of determination 14. Regression analysis

Multiple-ChoiceSelf-Test

1.C 2. C 3. D 4. B 5. B 6. B 7. D 8. A 9. A 10. B

11.B 12. A 13. A 14. A 15. A 16. A 17. C 18. A

1.Frequency Distribution Table.

 Speed Frequency Relative Frequency 62 1 0.05 64 3 0.15 65 4 0.2 67 3 0.15 68 2 0.1 70 2 0.1 72 1 0.05 73 1 0.05 76 1 0.05 79 1 0.05 80 1 0.05

2.Class Interval Frequency.

 Class interval Frequency Relative frequency 50-54 0 0 55-59 0 0 60-64 4 0.2 65-69 9 0.45 70-74 4 0.2 75-79 2 0.1 80-84 1 0.05 85-89 0 0 90-94 0 0 95-99 0 0

3. A histogram is suitable because it graphically represents thenumerical data distribution

4. Mean = 68.35

Median=67

Mode= 65

Thedistribution is skewed because there is no frequency above of morethan one on the speed above 70.

5.(a) Mean= 7.3

Median=8.5

Mode= 11

(b) Mean= 4.83

Median=5

Mode=5

(c) Mean= 6.1667

Median=6.5

Mode=3 and 8

(d) Mean = 5.5

Median=6

Mode=6

6.(a) Range =8

Standarddeviation =2.2

(b) Range= 8

Standarddeviation = 2.2

(c) Range= 80

Standarddeviation= 22

(d) Range =0.8

Standarddeviation = 0.22

(e) Range =800

Standarddeviation = 220

Reference

Garrett,H. E. (1966).&nbspStatisticsin psychology and education.New York: McKay