# Res 342 Week 4 Quiz

Topics: Statistics, Pontiac Sunbird, Normal distribution Pages: 2 (445 words) Published: February 1, 2011
Week 4 Quiz
RES 342

1.Describe in your own words what an ANOVA test is and what it can be used for in business research. The ANOVA test analysis variance and finds out if the means of several groups are equal to each other or different. In business research and ANOVA test can be used to test if the profits of three companies, located in different regions, are equal to each other during the holiday shopping season. 2.If we have three or more population means to compare, why can’t we test them two at a time until we exhaust all possible combinations? Testing two at a time would be very time consuming. Using an ANOVA test allows greater effiecencey than using and reusing a two-sample t-test when dealing with three or more populations.

3.Tedko Associates is a marketing research firm that specializes in comparative shopping. Tedko is hired by General Motors to compare the selling prices of Pontiac Sunbird with Chevy Cavalier. Posing as a potential customer, a representative of Tedko visited 8 Pontiac dealerships and 6 Chevrolet dealerships and obtained quotes on comparable cars. The standard deviation for the selling prices of 8 Pontiac Sunbirds is \$350 and on six Cavaliers, \$290. At the 0.01 significance level do Pontiac Sunbirds exhibit greater variance in quotes than Cavaliers?

Ho: Pontiac variance is less than or equal to Cavaliers variance Ha: Pontiac variance is greater than Cavaliers variance
The F-statistic = 350 /290 =1.4566
Numerator d.f. = 8 – 1 = 7
Denominator d.f. = 6 – 1 = 5
The critical value = F (0.01, 7, 5) = 10.455
The F-statistic is less than the critical value
The null hypothesis is rejected

4.A physician who specializes in weight control has three different diets she recommend. As an experiment, she randomly selected 15 patients and then assigned 5 to each diet. After three weeks, the following weight losses in pounds were noted. At the 0.05 significance level, can she conclude that there is a difference in the...

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