A copy editor thinks the standard deviation for the number o
A copy editor thinks the standard deviation for the number of pages in a romance novel is less than 6. A sample of 25 novels has a standard deviation of 9 pages. A= 0.05, is it what the copy editor hypothesizes? Show graph.
A copy editor thinks the standard deviation for the number of pages in a romance novel is less than 6. A sample of 25 novels has a standard deviation of 9 pages. A= 0.05, is it what the copy editor hypothesizes? Show graph.
Solution
The question is comparison of sample std deviation with that of population std deviation
H0: sigma s = 6
Ha: sigma s not equals 6
Sample size n =25
std dev = s = 9
Alpha = 0.05
F = s1^2/s2^2 = 81/36 =2.25
p value =0.00053
As p value <0.05 we reject null hypothesis
That is there is statistically significant different between sample std deviation and hypothestical 6.
