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(HW_3_2) Successful TV advertising depends on being able to get viewers to recall the specific brand being advertised. Two groups of randomly selected students are shown the TV ads for 10 products. One groups saw the TV ads with some sexual content, the other saw the TV ads rated for general audience. One week after seeing the ads each students was asked to name the specific brands which they saw on TV. The mean and SD of the number of correct answers for each group are given in the table below.

Calculate SE(X₁_bar - X₂_bar), the standard error of the differences of the sample means for the two groups
Calculate the two standard error interval for the difference of the two population means m₁ - m₂
Write a one paragraph report summarizing your conclusions from the analysis of these data.

Sexual Content Ads	n₁=53	X₁_bar=7.9	S₁=1.82
General Audience Ads	n₂=60	X₂_bar=4.3	S₂=1.53

(HW_3_3) Five fair, but unusual, octahedral (8 face) dice are rolled twice. Let Y be the random variable representing the total sum from this experiment (each die turns up an integer value between 1 and 8). Find the expected value of Y, m_Y, and the standard deviation of Y, s_Y. Suppose, we carry this experiment (rolling five dice twice) 9 times. What would be approximately the distribution of the sample average, Y¯? What are the mean and the standard deviation of the sample average? [Note: Not all types of dice, any number of faces, are possible. For a nice description of which ones that are possible see the following web-page.]

FOR 6520 Winter 2003