Question

1.a)A researcher obtains a sample of n= 25 adults who are between the ages of 65...

1.a)A researcher obtains a sample of n= 25 adults who are between the ages of 65 and 75. The researcher measures cognitive performance for each individual before and after a two-month program in which participants receive daily doses of a blueberry supplement. The results show an average increase in performance of MD= 8, with SS = 1200.

Does the result support the conclusion that the blueberry supplement significantly increase cognitive performance? Use a one-tailed test with α = .01

The alternative hypothesis in words is

Group of answer choices

a. The blueberry supplement does not change cognitive performance

b. The blueberry supplement changes cognitive performance

c. Cognitive performance after taking the supplement is not significantly higher than before taking the supplement.

d. Cognitive performance after taking the supplement is significantly higher than before taking the supplement.

1b)The null hypothesis in symbols is

Group of answer choices

a. H0: µ1= µ2

b. H0: µ1> µ2

c. H0: µD= 0

d. H0: µD≠ 0

e. H0: µD> 0

f. H0: MD = 7.4

g. H0: MD ≠ 7.4

h. H0: µD≤ 0

1c)The critical t-value is

1d)e t-statistic is

1e)

Your decision is

Group of answer choices

a. Reject the null hypothesis and conclude that cognitive performance after taking the supplement is significantly higher than before taking the supplement

b. Reject the null hypothesis and conclude that cognitive performance after taking the supplement is not significantly higher than before taking the supplement

c. Fail to reject the null hypothesis and conclude that cognitive performance after taking the supplement is significantly higher than before taking the supplement

d. Fail to reject the null hypothesis and conclude that cognitive performance after taking the supplement is not significantly higher than before taking the supplement

1f)

Construct a 95% confidence interval to estimate the average cognitive performance improvement for the population of older adults.

The lower boundary is

1g)

The upper boundary of the confidence interval you constructed in the previous question is

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