Question

You want to test whether or not the following sample of 30 observations follows a normal distribution. The mean of the sample equals 11.83 and the standard deviation equals 4.53.

2	3	5	5	7	8	8	9	9	10
11	11	12	12	12	12	13	13	13	14
15	15	15	16	16	17	17	18	18	19

The p-value is

a. between .025 and .05.

b. greater than .1.

c. between .05 and .1.

d. less than .005.

Answer 1

Answer : (b) (p value is greater than 0.1)

Applying the one sample t-test, with the value t as

t= (sample mean – hypothesized mean) / standard error of sample mean

sample mean (given) = 11.83

standard deviation = 4.53

n =30

hypothesized mean based on the 30 samples = summation of the values given in the table / n = 11.43

Applying all the values for the t test : t-statistic = 0.484 ;

Comparing the values of the t distribution table, thus the p value = 0.6323 (at 95% of confidence level)