STAT6160 Data Analytics For Business Assessment
- Subject Code :
STAT6160
- Country :
Australia
Question 1 (Total 9 Marks)
Mean entry-level salaries for college graduates with electrical engineering degrees and mechanical engineering degrees are believed to be approximately the same. A recruiting office thinks that the mean electrical engineering salary is actually greater than the mean mechanical engineering salary. The recruiting office randomly surveys 80 entry level electrical engineers and 100 entry level mechanical engineers. The data is provided in the file Question1.csv.
Conduct a hypothesis test to determine if you agree that the mean entry-level electrical engineering salary is greater than the mean entry-level mechanical engineering salary through the following six steps:
- What are the hypotheses to test whether the mean entry-level electrical engineering salary is greater than the mean entry-level mechanical engineering salary? Define the appropriate parameters. [2 Marks]
- What are the assumptions that you should made in using this test? Are they reasonable in this case? [2 Marks] (iii) What is the test statistic? [1 Mark]
- What is the null distribution? [1 Mark]
- What is the p-value? [1 Mark]
- Write a conclusion. [2 Marks]
Question 2 (Total 9 Marks)
A cheese manufacturer is seeking to determine whether two different kinds of packaging of a certain kind of cheese differ in their ability to protect cheese from mould. To do so, 80 equalsized pieces of cheese are cut from one randomly selected block, 40 are packaged by Method A and 40 are packaged by Method B. At 40 different locations, one Method A pack and one Method B pack are left until mould appears. The results (in days) before mould appears are provided in the file Question2.csv.
Implement the following six steps to test whether there is a difference, at a 5% significance level, between the abilities of the two different kinds of packaging to protect the cheese from mould.
- Define the parameters and state the null and alternative hypothesis. [2 Marks]
- Check the assumptions for this hypothesis test. [2 Marks]
- Find the test statistic. [1 Mark]
- State the null distribution. [1 Mark]
- Calculate the p-value. [1 Mark]
- Write the conclusion in plain language. [2 Marks]
Question 3 (Total 7 Marks)
A video game developer is testing a new game on three different groups. Each group represents a different target market for the game. The developer collects scores from a random sample from each group. The results are provided in the file Question3.csv.
The developer would like to test if there is a difference between the population mean scores of the three different groups, at a 5% significance level. In retrospect, we assume that the scores of each group are approximately normally distributed.
- Define the appropriate parameters and write down the null and alternative hypotheses. [2 Marks]
- What is the test statistic? [1 Mark]
- What is the null distribution? [1 Mark]
- What is the p-value? [1 Mark]
- Express your conclusion to the experiment. [2 Marks]