Digital camers have taken over the majority of the point-and-shoot camera market
ID: 1254311 • Letter: D
Question
Digital camers have taken over the majority of the point-and-shoot camera market. One of the important features of a camera is the battery life as measured by the number of shots taken until the battery needs to be recharged. The data file Digitalcameras contain the battery life of 31 subcompact cameras and 15 compact cameras(data extracted from "Cameras,".a. Assuming that the population variances from both types of digital camersa are equal, is there evidence of a difference in the mean battery life between the two types of digital camers (a=0.05) and also determine the p-value in and interpret its meaning
Explanation / Answer
Here is the explanation:
Test statistic: F S STAT = = 1.0389
Decision: Since FSTAT = 1.0389 is lower than the upper critical value of 2.7324, do
not reject H0. There is not enough evidence of a difference in the variability of the
battery life between the two types of digital cameras.
(b) p-value = 0.9789. The probability of obtaining a sample that yields a test statistic
more extreme than 1.0389 is 0.9789 if the null hypothesis that there is no difference
in the two population variances is true.
(c) The test assumes that the two populations are both normally distributed.
(d) Based on (a) and (b), a pooled-variance t test should be used