Randolph College
Department of Mathematics and Computer Science

 

Homework # 17 - MATH 2227


The problems on this homework must be done alone.  The honor code is in effect.

 First name:   Last name:


 

A business association of 10 local businesses is trying to determine whether or not collective advertizing on social media is bringing more customers in to shop. Each business keeps track of customers for one week where they don't advertize, and then a second week where they do. They discover that the average increase in customers from the first week to the second is 100, and the standard deviation of these differences is 150. Conduct a test at the 5% significance level.

 

1.  Compute the t-statistic.

a.  1.67

b.  2.11

c.  3.40

d.  5.23

d.  6.89

 

2.  Into what range does your p-value fall.

a.  Between 10% and 25%

b.  Between 7.5% and 10%

c.  Between 5% and 7.5%

d.  Between 2.5% and 5%

d.  Between 1% and 2.5%

 

3.  In the above test, if \(\alpha = 5%\), what should we do?

a.  Accept the null hypothesis.

b.  Fail to reject the null hypothesis.

c.  Reject the null hypothesis.

 

4.  Interpret your results?

a.  At the 5% significance level we don't have sufficient reason to think that advertizing works.

b.  At the 5% significance level we do have sufficient reason to think that advertizing works.