Question

Excel Questions

Q1. What is the sample mean of income?

Q2. What is the sample standard deviation of income? For questions 3 and 4, construct a 95% confidence interval for the average house price.

Q3. Enter the low end of the interval.

Q4. Enter the high end of the interval

Q5. The the typical household income in Indiana is $52,314. Suppose we want to test whether the people in this town earn a different amount on average. Find the p-value for this hypothesis test.

Q6. What is the highest confidence level at which you would reject the null hypothesis?

Q7. Suppose we want to test whether the two towns have the same unemployment rate. Find the p-value for this hypothesis test.

Q8. What is the highest confidence level at which you would reject the null hypothesis

Q9. Suppose we want to test whether runner 1 is faster than runner 2. Find the p-value for this hypothesis test.

Q10. What is the highest confidence level at which you would reject the null hypothesis

You run a small business with the following data for the last 100 days. Here is a summary for all of the variables:

Sales: Your revenue in dollars for the day.

Ads: The amount that you have spent on advertising.

Weekend: Equals 1 if it is on a weekend and 0 if not.

Holiday: Equals 1 if it is on a holiday and 0 if not

Run a regression with sales as your independent variable and ads, weekend and holiday as your dependent variables.

Q11. What is the p-value for the ads coefficient

Q12. What is the highest confidence level at which you would reject the null hypothesis that ads don't affect sales (use the dropdown list)?

Q13. What is the coefficient for ads?

Q14. Using this model, predict your sales for a day where you have spent $100 on ads, it is not a weekend and it is a holiday.

Run the same regression but with the natural logarithm of ads instead of ads.

Q15. What is the coefficient for ads now?

Q16. Which model performs better overall?

You run a store where you have data on the temperature outside and the amount that you spent on heating over the last 50 days.

Q17. What is the correlation between temperature and heating costs in this sample?

Q18. Find the test statistic for the hypothesis test for whether temperature and heating cost are correlated. (hint: look at CPA 14 part 1 for guidance)

Q19. What is the p-value for this hypothesis test? (hint: The t.dist functions require a positive value for x. Be sure to take the absolute value of the t-score using the abs function)

Q20. What is the highest confidence level at which you would reject the null hypothesis?

Income	House Price
45724.50469	229669.22
64748.13922	321863.96
41116.40033	190247.32
49956.66181	221302.71
51784.69088	251299.13
47279.82381	197807.47
46923.55034	214079.92
58268.95352	277778.4
53413.40914	252928.77
63197.50762	315495.02
57404.75569	257250.09
80259.24003	420311.04
62592.35376	308995.72
47075.57529	207582.14
44444.71254	209651.72
56905.0827	278069.72
46043.99216	204041.9
45006.97844	179014.46
47630.56804	204106.32
49163.85754	218079.21
56087.47271	261491.14
41544.30524	178800.74
58855.80062	273530.03
62347.41604	325613.97
57244.67281	281427.6
61584.49916	290085.08
58997.79879	252881.31
64329.8906	305541.83
52245.42395	260409.85

Answer 1

1)

Income
Mean	54213.03577
Standard Error	1628.977904
Median	53413.40914
Mode	#N/A
Standard Deviation	8772.31448
Sample Variance	76953501.33
Kurtosis	1.097222157
Skewness	0.780953031
Range	39142.8397
Minimum	41116.40033
Maximum	80259.24003
Sum	1572178.037
Count	29

1)

Mean	54213.03577

2)

Standard Deviation

8772.31448

3) and 4)

5)