Question 1
It is widely assumed that the average cost to produce a film is $60 million. A random sample of 15 action movies was selected and they had an average production cost of $62.3 million with a standard deviation of $3.25 million. At the 0.05 level of significance, can it be concluded that it costs more than average to produce an action movie?
Question 2
Suppose a fair six-sided die is tossed to see if it fair. We roll the die 300 times and observe the frequency of occurrence of each of the faces. Since the die contains six sides, we expect that the number on each side will occur 50 times. The following frequencies were observed:
Face value Occurrence
1 42
2 55
3 38
4 57
5 64
6 44
Conduct a Chi-sq Goodness of Fit test to see if the die should still be considered fair.
Question 3
An analyst wanted to analyze the relationship between the speed of a car (x) measured in mph and its gas mileage (y). As an experiment a car is operated at several different speeds and for each speed the gas mileage is measured. These data are shown below.
Speed 25 35 45 50 60 65 70
Gas Mileage 40 39 37 33 30 27 25
What is the dependent variable?
What is the independent variable?
Question 4
The following output was generated using statistical software.
Coefficients Standard Error t Stat P-value
Intercept 50.65625 1.891010513 26.79 0.13529
Speed -0.353125 0.036201476 -9.754 0.00019
List the prediction equation for gas mileage based on speed.
What gas mileage is expected for a vehicle traveling 80 mph?
Is speed a good predictor of gas mileage based on the output? Explain your answer.