Question

	# of Cheeseburgers-Male	# of Cheeseburgers-Female
1	6	11
2	18	25
3	35	18
4	19	44
5	47	69
6	2	1
7	18	19
8	23	16
9	42	28
10	55	33
11	22	17
12	26	21
13	33	2
14	21	4
15	7	2
16	58	27
17	44	18
18	44	19
19	35	13
20	19	17

Dr. Wendy McDonald has been conducting a series of studies on the consumption of cheeseburgers
Here, she sets up an experiment where she samples 20 random men and 20 random women that she met at McDonald's and surveys their annual consumption of cheeseburgers
She hired you as a statistical consultant.  Analyze these data and draw the most reasonable conclusion(s)
What scientific question(s) are you trying to answer?
What statistical method(s) have you used, and why?
List your null hypotheses and alternate hypotheses, if any.
Put any important values such as test statistics, p-values etc, here:
Can you identify a source of bias in this experiment?

Answer 1

Objective of the study is: To check whther there is gender wise difference in consumption of cheeseburgers.

First will calculate mean and standard deviation for both the genders

sample means are shown below:

and

sample standard deviations are:

s1​=16.04 and s2=15.77

and sample size= n1= n2= 20

Null and Alternative Hypotheses

The following null and alternative hypotheses need to be tested:

Ho: μ1​ = μ2 : There is no genderwise significant difference in cheeseburgers consumers

Ha: μ1​ ≠ μ2 : There is genderwise significant difference in cheeseburgers consumers

This corresponds to a two-tailed test, for which a t-test for two population means, with two independent samples, will be used.

Rejection Region

Will consider significance level as α=0.05 and the degrees of freedom are df=38

Hence, it is found that the critical value for this two-tailed test is tc=2.024 for α=0.05 df=38

The rejection region for this two-tailed test is R={t:∣t∣>2.024}.

Test Statistics

Since it is assumed that the population variances are equal, the t-statistic is computed as follows:

t = 1.69

Decision about the null hypothesis

Since it is observed that ∣t∣=1.69 ≤ tc=2.024 it is then concluded that the null hypothesis is not rejected.

Using the P-value approach: The p-value is = 0.0992 ≥ 0.05, it is concluded that the null hypothesis is not rejected.

Conclusion

It is concluded that the null hypothesis Ho is not rejected. Therefore, there is not enough evidence to claim that the population mean μ1​ is different than μ2, at the 0.05 significance level.

Hence we can say that, There is no genderwise significant difference in cheeseburgers consumers.

Can you identify a source of bias in this experiment?

To answer this question, given information in problem looks incomplete (specifically second sentence of problem looks incomplete).