According to Communications Industry Forecast and Report, published by Veronis S
ID: 2960198 • Letter: A
Question
According to Communications Industry Forecast and Report, published by Veronis Suhler Stevenson of New York, NY, the average person watched 4.66 hours of television per day in 2002. A random sample of 20 people gave the following number of hours of television watched per day for last year. At the 10% significance level, do the data provide sufficient evidence to conclude that the amount of television watched per day last year by the average person differed from that in 2002. (Note: same average x (bar on top) = 4.835 hours and s=2.291 hours.)
Explanation / Answer
Given xbar = 4.835, s=2.291,n=20
The test hypothesis is
Ho: = 4.66
Ha: not equal to 4.66
The test statistic is
t=(xbar - )/(s/n)
=(4.835 - 4.66)/(2.291/sqrt(20))
=0.34
Given a=0.1 , the critical value is |t(0.05, df=n-1=19)|=1.729 (check student t table)
Since t=0.34 < 1.729, we do not reject Ho.
So we can not conclude that the amount of television watched per day last year by the average person is differed from that in 2002