Question

 

Complete a t-test using the data collected during the first week of class (i.e., the question you asked classmates). You can compare groups via gender or major, depending on your hypothesis. For example, as I mentioned, last year an MLS student asked his classmates how many times they had seen Star Wars. He hypothesized that there was a significant difference between MLS and DEHS students, so he compared those two groups.

What type of inferential test should you use and why?

Using the A-B-C-D (A: Data summary B: Set up Hypothesis C: Test Statistic D: Test Hypothesis and draw conclusion) format demonstrated in class, test the null hypothesis. (Use ? = .05)

Here is my data collected. Please check my math!

DEHS MLS

Ale	3	-6.25	39.0625				Jericho	3	-7	49
Megan	4	-8	64				Elexis	9	-9	81
Sarah	20	11.75	138.0625				Amanda	5	-4.16667	17.36111
Aspen	6	3.127719	9.782624				David C	2	-1.02765	1.056065
Christina	10	10	100				Askalu	2	2	4
Yahaire	20	20	400				Samantha G	25	25	625
Francesca	4	4	16				Candice	25	25	625
Maribel	10	10	100				Anahy	10	10	100
Ashley	20	20	400				Kevin	10	10	100
Rebecca	8	8	64				Zachary M	10	10	100
Priscilla	2	2	4				Francisco	3	3	9
Elissa	4	4	16				Miquel	10	10	100
							Jessica	5	5	25
Sum	111	78.62772	1350.908				Zachary P	14	14	196
Average	9.25						Jennifer S	25	25	625
n	12	12	12				Marco	3	3	9
Variance	8.25						Alejandra	2	2	4
s:	2.872281						Jennifer R	20	20	400
							SUM:	183	142.8057	3070.417
							Average:	10
							n	18	18	18
							Variance	9.166667
							s:	3.02765

Answer 1

We have given two groups which are DEHS and MLS.

Suppose we compare first column of both groups then data will be :

dehs	mls
3	3
4	9
20	5
6	2
10	2
20	25
4	25
10	10
20	10
8	10
2	3
4	10
	5
	14
	25
	3
	2
	20

Here we have to test the hypothesis that,

H0 : mu1 = mu2 Vs H1 : mu1 not= mu2

where mu1 and mu2 are two population means of dehs and mls.

Assume alpha = level of significance = 0.05

We can do here two sample t-test assuming equal variances.

We can do two sample t-test in excel.

steps :

ENTER data into excel sheet --> Data --> Data analysis --> t-test : Two sample assuming equal variances --> ok --> Variable 1 range : select dehs column --> Variable 2 range : select mls column --> Hypothesized mean difference : 0 --> Labels --> Output range : select one empty cell --> ok

t-Test: Two-Sample Assuming Equal Variances
	dehs	mls
Mean	9.25	10.16667
Variance	48.56818	69.44118
Observations	12	18
Pooled Variance	61.24107
Hypothesized Mean Difference	0
df	28
t Stat	-0.31431
P(T<=t) one-tail	0.377808
t Critical one-tail	1.701131
P(T<=t) two-tail	0.755617
t Critical two-tail	2.048407

Test statistic = -0.31

P-value = 0.7556

P-value > alpha

Accept H0 at 5% level of significance.

COnclusion : There is sufficient evidence to say that two population means are equal.