Question

Use the following information to run a t-Test in EXCEL.

Write a paragraph description about the information you found and the conclusions you can draw.  

"To Breakfast or Not to Breakfast?" by Richard Ayore

In the American society, birthdays are one of those days that everyone looks forward to. People of different ages and peer groups gather to mark the 18th, 20th, …, birthdays. During this time, one looks back to see what he or she has achieved for the past year and also focuses ahead for more to come.

If, by any chance, I am invited to one of these parties, my experience is always different. Instead of dancing around with my friends while the music is booming, I get carried away by memories of my family back home in Kenya. I remember the good times I had with my brothers and sister while we did our daily routine.

Every morning, I remember we went to the shamba (garden) to weed our crops. I remember one day arguing with my brother as to why he always remained behind just to join us an hour later. In his defense, he said that he preferred waiting for breakfast before he came to weed. He said, “This is why I always work more hours than you guys!”

And so, to prove him wrong or right, we decided to give it a try. One day we went to work as usual without breakfast, and recorded the time we could work before getting tired and stopping. On the next day, we all ate breakfast before going to work. We recorded how long we worked again before getting tired and stopping. Of interest was our mean increase in work time. My brother insisted that it was more than two hours.

Work hours with breakfast	Work hours without breakfast
8	6
7	5
9	5
5	4
9	7
8	7
10	7
7	5
6	6
9	5

What would this look like in Excel?

What is the interpretation of data?

Answer 1

Sl . No	Work hours with breakfast	Work hours without breakfast
1	8	6
2	7	5
3	9	5
4	5	4
5	9	7
6	8	7
7	10	7
8	7	5
9	6	6
10	9	5
Number of observations	10	10
Mean	7.8	5.7
Sample std. Dev	1.549193338	1.059349905

After giving the data in excel in two columns now goto Data menu in that goto Data Analysis tool

If we click on that Data Analysis tool we can get window with different options in that we select t-test two sample assuming equal variances, Then we select the data into two data sets and provide the mean difference as 0.

Here let us assume

= population mean of Work hours with breakfast

= population mean of Work hours without breakfast

Hypothesis:

H₀ : (Eating breakfast does not affect the working hours)

H₁ : (Eating breakfast does affect the working hours)

level of significance = 0.05

Excel results

t-Test: Two-Sample Assuming Equal Variances
	Work hours with breakfast	Work hours without breakfast
Mean	7.8	5.7
Variance	2.4	1.122222
Observations	10	10
Pooled Variance	1.761111
Hypothesized Mean Difference	0
df	18
t Stat	3.538433
P(T<=t) one-tail	0.001174
t Critical one-tail	1.734064
P(T<=t) two-tail	0.002348
t Critical two-tail	2.100922

Our test is a one tail test. From the result of excel

for one tail t-test p-value is 0.001 which is less than level of significance = 0.05, hence we reject null hypothesis and we conclude that there is significant difference between working hours with and without breakfast.