Question

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 *M _{D}*= 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

Answer #1

A researcher obtains a sample of n= 16 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= 7.4, with SS = 1215. Does the result support the conclusion
that the blueberry supplement significantly increase cognitive
performance? Use a one-tailed test with α = .05
(A)...

A researcher obtains a sample of n= 16 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= 7.4, with SS = 1215.
Does the result support the conclusion that the blueberry
supplement significantly increase cognitive performance? Use a
one-tailed test with α = .05
a)The...

1a)
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researcher used a sample of n =16 adults between the ages of 40 and
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A researcher used a sample of n= 25 adults between the
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