Question

7.3.11 The Cholesterol Level data sets give cholesterol levels of heart attack patients. Cholesterol measures are taken 2, 4, and 14 days after a patient has suffered a heart attack. Is there a significant difference between day 2 cholesterol measures and day 4 cholesterol measures? Use an appropriate applet to carry out a theory-based test and find a 95% confidence interval for the difference. Use the data file CholesterolLevel_day2-4. Make sure to confirm that validity conditions are met to conduct a theory-based test for this question. State the null and alternative hypotheses using day 2 cholesterol measures and day 4 cholesterol measures. The theory-based p-value is confidence interval for the difference in cholesterol measurements (day 2 day 4) is ( *1 (rounded to 3 decimal places) and a theory-based 95% 12, 3) (rounded to 2 decimal places) Answer *1: the absolute tolerance is +/-0.02 Answer *2: the absolute tolerance is /-0.02 Answer *3: the absolute tolerance is +/-0.02 Based on the resulting p-value and the confidence interval, we have strong evidence that the long-term mean cholesterol level on day 2 is than on day 4.

Here is the data file:

day2    day4
270     218
236     234
210     214
142     116
280     200
272     276
160     146
220     182
226     238
242     288
186     190
266     236
206     244
318     258
294     240
282     294
234     220
224     200
276     220
282     186
360     352
310     202
280     218
278     248
288     278
288     248
244     270
236     242

Answer 1

a)
option A)
Null: The average difference in cholesterol levels between day 2 and 4 is 0. Alt: The average difference is not 0.

b)
Paired T-Test and CI: day2, day4

Paired T for day2 - day4

             N    Mean StDev SE Mean
day2        28 253.93 47.71     9.02
day4        28 230.64 46.97     8.88
Difference 28   23.29 38.28     7.23

95% CI for mean difference: (8.44, 38.13)
T-Test of mean difference = 0 (vs ≠ 0): T-Value = 3.22 P-Value = 0.003

p-value = 0.003

95% CI for mean difference: (8.44, 38.13)

c)

Based on the resulting p-value and the confidence interval, we

do

have strong evidence that the long-term mean cholesterol level on day 2 is

higher

than on day 4.

please rate...