Question

1. An advertising firm commissioned a study to determine whether the content of TV shows affected the ability of viewers to remember brand names from commercials. Ninety-eight (98) randomly selected people watched a show with violent content. Of the nine commercials shown, they were able to remember an average of 2.84 brand names with a sample standard deviation of 1.51. Ninety-six (96) randomly selected people watched a show with neutral (non-violent) content. Of the same nine commercials shown, they were able to remember an average of 3.97 brand names with a sample standard deviation of 1.62.

1. Carry out by hand a 2-sample t test at the 5% level to test for a difference in brand recollection between the violent and neutral show viewers. (Compute the test statistic and reach the result by using N(0, 1) to estimate the p-value.)

Answer 1

The hypothesis being tested is:

H₀: µ₁ = µ₂

H₁: µ₁ ≠ µ₂

VC	NVC
2.84	3.97	mean
1.51	1.62	std. dev.
98	96	n
	192	df
	-1.13000	difference (VC - NVC)
	2.45046	pooled variance
	1.56539	pooled std. dev.
	0.22479	standard error of difference
	0	hypothesized difference
	-5.027	t
	1.14E-06	p-value (two-tailed)

The test statistic is -5.027.

The p-value is 0.0000.

Since the p-value (0.0000) is less than the significance level (0.05), we can reject the null hypothesis.

Therefore, we can conclude that there is a difference in brand recollection between the violent and neutral show viewers.