Question

4. A study of the effect of television commercials on 12-year-old children measured their attention span, in seconds. The commercials were for clothes, food, and toys.

Clothes	Food	Toys
35	42	56
32	39	42
34	39	53
35	55	60
28	47	63
31	42	53
17	34	48
31	43	58
20	57	47
	47	51
	44	51
	54

  Click here for the Excel Data File

1. Complete the ANOVA table. Use 0.05 significance level. (Round the SS and MS values to 1 decimal place and F value to 2 decimal places. Leave no cells blank — be certain to enter "0" wherever required. Round the df values to nearest whole number.)
2. Find the values of mean and standard deviation. (Round the mean and standard deviation values to 3 decimal places.)
3. Is there a difference in the mean attention span of the children for the various commercials?
4. Are there significant differences between pairs of means?

Item	Length
Clothes	35
Clothes	32
Clothes	34
Clothes	35
Clothes	28
Clothes	31
Clothes	17
Clothes	31
Clothes	20
Food	42
Food	39
Food	39
Food	55
Food	47
Food	42
Food	34
Food	43
Food	57
Food	47
Food	44
Food	54
Toys	56
Toys	42
Toys	53
Toys	60
Toys	63
Toys	53
Toys	48
Toys	58
Toys	47
Toys	51
Toys	51

Answer 1