For the next four problems, please provide the following:

1. Identify the independent variable(s)- if any (and define them precisely and indicate whether they are qualitative or quantitative)
2. Identify the dependent variable - if any (and define them precisely and indicate whether they are qualitative or quantitative)
3. Identify the type of analysis that is appropriate: Two sample t-test (identify pooled variance vs. paired), Chi-square test (identify test of proportions or test of independence), ANOVA (identify one factor, randomized block, or 2-factor with replication), Correlation, or Regression

1. Your firm is having quality problem with the production of plastic automotive parts: there are too many defectives. One of your engineers thinks that it's because the temperature of the process is not controlled carefully enough. Another engineer is sure that it's because the assembly line is being shut down too often for unrelated reasons. You have decided to analyze the problem and have come up with figures for the percent defective each day (as a measure of temperature control), and the number of assembly line stoppages each day. You are interested in finding out which engineer is right.
2. To test the effectiveness of a business school preparation course, 8 students took a general business test before and after the course. The dean is interested in making a recommendation whether taking the course will result in a statistically significant improvement in student test score.
3. Many companies use well-known celebrities in their ads, while other companies create their own spokespersons (such as Maytag repairman). A marketing researcher is interested in investigating the relationship between gender of the spokesperson and brand awareness. Three hundred television viewers were asked to identify the products advertised by celebrity spokesperson.
4. Jacobs Chemical Company will purchase new mixing machines from one of three manufacturers, based on which manufacturer's machine has the fastest mixing time. The company obtained data for the time to mix 20 standardized batches of material from each of the three manufacturers. Based on a statistical analysis of the average mixing time of the three machines, the company will makes its choice.