1- At LLD Records, some of the market research of college students is done during promotions on college campuses, while other market research of college students is done through anonymous mail, phone, internet, and record store questionnaires. In all cases, for each new CD the company solicits an "intent-to-purchase" score from the student, with being the lowest score ("no intent to purchase") and being the highest score ("full intent to purchase").
The manager finds the following information for intent-to-purchase scores for a soon-to-be-released CD
Group Sample size Sample Mean Sample variance
On campus 25 64.3 116.1
By mail 25 66.1 82.7
By phone 25 60.2 94.4
By internet 25 62.5 137.7
In a store 25 68.2 78.5
The manager's next step is to conduct a one-way, independent-samples ANOVA test to decide if there is a difference in the mean intent-to-purchase score for this CD depending on the method of collecting the scores.
Answer the following, carrying your intermediate computations to at least three decimal places and rounding your responses to at least one decimal place.
a- What's the value of the mean square for error (the "between groups" mean square) that would be reported in the ANOVA test?
b- What's the value of the mean square for treatment (the "within groups" mean square) that would be reported in the ANOVA test?