Question

Use SPSS to compute the mean, standard deviation, variance, and range for the following sets of scores. Name the scores, Scores.

a. 8, 2, 6, 12, 4, 7, 4, 10, 13, 15, 11, 12, 5

b. 7.2, 2.3, 5.4, 2.3, 3.4, 9.2, 7.6, 4.7, 2.8, 6.5

c. 23, 65, 47, 38, 86, 57, 32, 66, 43, 85, 29, 40, 42

d. 212, 334, 250, 436, 425, 531, 600, 487, 529, 234, 515

e. Does SPSS use N or N ⫺ 1 in the denominator when computing the standard deviation? How could you determine the correct answer without looking it up or asking someone?

Answer 1

Result:

Use SPSS to compute the mean, standard deviation, variance, and range for the following sets of scores. Name the scores, Scores.

a. 8, 2, 6, 12, 4, 7, 4, 10, 13, 15, 11, 12, 5

b. 7.2, 2.3, 5.4, 2.3, 3.4, 9.2, 7.6, 4.7, 2.8, 6.5

c. 23, 65, 47, 38, 86, 57, 32, 66, 43, 85, 29, 40, 42

d. 212, 334, 250, 436, 425, 531, 600, 487, 529, 234, 515

SPSS data:

SPSS command:

DESCRIPTIVES VARIABLES=a b c d

/STATISTICS=MEAN STDDEV VARIANCE RANGE MIN MAX.

SPSS output:

Descriptive Statistics
	N	Range	Minimum	Maximum	Mean	Std. Deviation	Variance
a	13	13.00	2.00	15.00	8.3846	4.07305	16.590
b	10	6.90	2.30	9.20	5.1400	2.43867	5.947
c	13	63.00	23.00	86.00	50.2308	20.22850	409.192
d	11	388.00	212.00	600.00	413.9091	135.70000	18414.491
Valid N (listwise)	10

e. Does SPSS use N or N - 1 in the denominator when computing the standard deviation? How could you determine the correct answer without looking it up or asking someone?

SPSS use sample Standard deviation formula which has n-1 in denominator.

For the variable a,

which is the SPSS output given

if n is used in denominator, then

which is different from spss output.