In: Statistics and Probability
A physical therapist developed a new yoga regimen specifically
for treating knee pain. He collected a random sample of chronic
knee pain patients from the hospital that underwent the new regimen
for 20 days. For each day of the study, the patients are asked to
rate their knee pain on a scale from 0-10; no pain to extreme pain,
respectively. Chronic knee pain sufferers typically report a 5 on
the pain scale. Below are the average knee pain scores for the
patients over the study. What can be concluded with an α of
0.01?
id | pain |
11 12 13 14 15 16 17 18 19 20 21 1 2 3 4 5 6 7 8 9 10 |
0 9 4 7 8 6 6 3 6 6 7 5 5 8 3 3 4 8 9 7 9 |
b)
Population: (Choose one)
1)pain 2)patients on the regimen 3)the hospital 4)chronic knee pain
sufferer 5) 20 days
Sample:
1)pain 2)patients on the regimen 3)the hospital 4)chronic knee pain
sufferer 5) 20 days
c) Input the appropriate value(s) to make a
decision about H0.
(Hint: Make sure to write down the null and alternative hypotheses
to help solve the problem.)
p-value = ;
Decision: Reject H0 or Fail to reject H0
d) Using the SPSS results,
compute the corresponding effect size(s) and indicate
magnitude(s).
If not appropriate, input and/or select "na" below.
d =____________ ; (Choose one) 1)na 2)trivial effect
3)small effect 4)medium effect 5)large effect
r2 =____________ ; (Choose one) 1)na 2)trivial
effect 3)small effect 4)medium effect 5)large effect
e) Make an interpretation based on the
results. (Choose one)
1)The new yoga regimen significantly worsens knee pain.
2)The new yoga regimen significantly improves knee pain.
3) The new yoga regimen is not significantly effective at treating knee pain.
one sample t test
b) population: All chronic knee pain sufferer
sample: 20 days
c)
Ho : µ = 5
Ha : µ > 5 (Right tail
test)
Level of Significance , α =
0.010
sample std dev , s = √(Σ(X- x̅ )²/(n-1) )
= 2.3934
Sample Size , n = 21
Sample Mean, x̅ = ΣX/n =
5.8571
degree of freedom= DF=n-1=
20
Standard Error , SE = s/√n = 2.3934/√21=
0.5223
t-test statistic= (x̅ - µ )/SE =
(5.8571-5)/0.5223= 1.6411
p-Value = 0.0582
[Excel formula =t.dist(t-stat,df) ]
Decision: p-value>α, Do not reject null
hypothesis
d)
Cohen's d= nA
r² = Na
e) 3) The new yoga regimen is not significantly effective at treating knee pain.