Question

In what ways do advertisers in magazines use sexual imagery to appeal to youth? One study classified each of 1509 full-page or larger ads as "not sexual" or "sexual," according to the amount and style of the dress of the male or female model in the ad. The ads were also classified according to the target readership of the magazine. Here is the two-way table of counts.

	Magazine readership
Model dress	Women	Men	General interest	Total
Not sexual	357	524	245	1126
Sexual	211	98	74	383
Total	568	622	319	1509

(a) Summarize the data numerically and graphically. (Compute the conditional distribution of model dress for each audience. Round your answers to three decimal places.)

	Women	Men	General
Not sexual
Sexual

(b) Perform the significance test that compares the model dress for the three categories of magazine readership. Summarize the results of your test and give your conclusion. (Use α = 0.01.Round your value for χ² to two decimal places, and round your P-value to four decimal places.)

χ2 =
P-value =

Conclusion

Fail to reject the null hypothesis. There is not significant evidence of an association between target audience and model dress.Reject the null hypothesis. There is significant evidence of an association between target audience and model dress.    Fail to reject the null hypothesis. There is significant evidence of an association between target audience and model dress.Reject the null hypothesis. There is not significant evidence of an association between target audience and model dress.

(c) All of the ads were taken from the March, July, and November issues of six magazines in one year. Discuss this fact from the viewpoint of the validity of the significance test and the interpretation of the results.

This is not an SRS. This gives us no reason to believe our conclusions are suspect.This is an SRS. This gives us reason to believe our conclusions might be suspect.    This is not an SRS. This gives us reason to believe our conclusions might be suspect.This is an SRS. This gives us no reason to believe our conclusions are suspect.

Answer 1

Tabulated Statistics: Model dress, Worksheet columns

Rows: Model dress   Columns: Worksheet columns

	Women	Men	General interest	All
Not sexual	357.000	524.000	245.000	1126
Expected count	423.836	464.130	238.034
Sexual	211.000	98.000	74.000	383
Expected count	144.164	157.870	80.966
All	568.000	622.000	319.000	1509

Cell Contents
      Count
      Expected count

Chi-Square Test

	Chi-Square	DF	P-Value
Pearson	72.756	2	0.0000

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b)

p-value =0.0000

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conclusion

.Reject the null hypothesis. There is significant evidence of an association between target audience and model dress.

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c) This is an SRS. This gives us reason to believe our conclusions might be suspect.