Question

1. A new low fat/carbohydrate diet was designed to assist with weight loss. From a population of obese people, 100 are randomly selected to go on the new diet, while another 100 are selected to eat a diet of a similar quantity of food but not as low in fats and carbohydrates. The weight loss of each of the 200 people are in the Excel file "Extra HW 1 Diet Study". Use 0.05 significance and answer the following.

   1. Whataretheappropriatehypothesestotestwhetherthereisevidenceforadifferencein mean weight loss between people who eat these diets?

   2. Findtheappropriatet-scoreandP-value.

   3. StatetheconclusionofthetestinanEnglishsentence.

      Lowfat	Regular
      8	6
      10	6
      10	5
      12	5
      9	2
      3	6
      11	10
      7	3
      9	9
      2	11
      21	14
      8	4
      9	10
      2	13
      2	3
      20	8
      14	8
      11	13
      15	9
      6	3
      13	4
      8	12
      10	6
      12	11
      1	12
      7	9
      10	8
      13	5
      14	8
      4	7
      8	6
      12	2
      8	6
      10	8
      11	5
      19	7
      0	16
      9	18
      10	6
      4	8
      11	13
      7	1
      14	9
      12	8
      11	12
      12	10
      4	6
      12	1
      9	0
      2	13
      4	11
      3	2
      3	8
      5	16
      9	14
      9	4
      4	6
      3	5
      5	12
      12	9
      3	11
      12	6
      7	3
      13	9
      11	9
      11	14
      13	2
      12	10
      18	4
      9	13
      6	8
      14	1
      14	1
      18	4
      10	9
      11	4
      7	1
      9	1
      7	5
      2	6
      16	14
      16	0
      11	7
      11	12
      3	9
      15	5
      9	9
      5	12
      2	7
      6	9
      5	8
      11	9
      14	8
      11	10
      6	5
      9	8
      4	0
      17	3
      20	4
      10	8

Answer 1

Sol:

perform t test for difference in means in excel

Install analysis toolapk in excel

Go to Data >Data analysis>T test assuming un equal variances we get

select the variable range

clcik ok

Output:

t-Test: Two-Sample Assuming Unequal Variances
	Lowfat	Regular
Mean	9.31	7.4
Variance	21.79182	16.28283
Observations	100	100
Hypothesized Mean Difference	0
df	194
t Stat	3.09539
P(T<=t) one-tail	0.001128
t Critical one-tail	1.652746
P(T<=t) two-tail	0.002256
t Critical two-tail	1.972268

Ho:

Ha:

exists a differencei n mean weight loss between people who eat these diets

alpha=0.05

From output;

t statistic=3.09539

df=194

p=0.002256

p<alpha

Reject Null hypothesis

Accept alternative hypothesis

Conclusion:

There is suffcient evidence at 5% level of significance to conclude that there a difference in mean weight loss between people who eat these diets.

In plain english it means

A new low fat/carbohydrate diet designed to assist with weight loss is suucessful,it can help with weight loss.