In: Statistics and Probability
Clinicians hypothesize there is a difference in learning self-care skills between two techniques. For 4 months the clinicians worked with mentally impaired individuals in which half were taught self-care skills through video imitation and the other half through physical guidance. At the end of the 4 months, individuals were asked to independently perform the self-care task and were rated on the level of required assistance where a higher score indicates more assistance. What can be concluded with an α of 0.05? The rating data are below.
video imitation | physical guidance |
10 10 17 11 11 14 11 14 16 |
15 13 16 11 19 21 16 14 20 |
a) What is the appropriate test
statistic?
---Select one--- (na, z-test, One-Sample t-test,
Independent-Samples t-test, Related-Samples t-test)
b)
Condition 1:
---Select one--- (physical guidance, 4 months, mentally impaired,
video imitation, self-care skills)
Condition 2:
---Select one--- (physical guidance, 4 months, mentally impaired,
video imitation, self-care skills)
c) Obtain/compute the appropriate values to make a
decision about H0.
(Hint: Make sure to write down the null and alternative hypotheses
to help solve the problem.)
critical value = ; test statistic =
Decision: ---Select one--- (Reject H0, Fail to reject
H0)
d) If appropriate, compute the CI. If not
appropriate, input "na" for both spaces below.
[ , ]
e) Compute the corresponding effect size(s) and
indicate magnitude(s).
If not appropriate, input and/or select "na" below.
d = ; ---Select one--- (na, trivial
effect, small effect, medium effect, large effect)
r2 = ; ---Select one---
(na, trivial effect, small effect, medium effect, large
effect)
f) Make an interpretation based on the
results.
a. Self-care skills improve when learned through physical guidance.
b. Self-care skills improve when learned through video imitation.
c. There is no significant self-care difference between video imitation and physical guidance.
Sr. No | video imitation | physical guidance |
1 | 10 | 15 |
2 | 10 | 13 |
3 | 17 | 16 |
4 | 11 | 11 |
5 | 11 | 19 |
6 | 14 | 21 |
7 | 11 | 16 |
8 | 14 | 14 |
9 | 16 | 20 |
Total | 114.000 | 145.000 |
Mean | 12.667 | 16.111 |
Var | 7.000 | 11.111 |
n | 9.000 | 9.000 |
Mean =
Var
a) What is the appropriate test
statistic?
Independent-Samples t-test
This is because the test is to compare two population means where the samples selected ae not same for both the data sets. Hence they are indpendent.
b)
Condition 1:
video imitation
Condition 2:
physical guidance
c) Obtain/compute the appropriate values to make a decision
about H0.
(Hint: Make sure to write down the null and alternative hypotheses
to help solve the problem.)
The cliician say that there is a difference not indicating a positive or a negative one. Hence, it is a two tailed test where the null hypothesis difference between means =0
(There is no difference between the ratings)
(There is a difference between the ratings)
We are testing at 0.05
critical value =
=
Critical value = 2.12 .........using t-dit tables with p = 2.5% and df = 9 + 9 - 2 = 16
; test statistic =
Where the null difference =
Where the pooled variance =
= 9.0556
Test stat =
Test Stat = -2.428
Since |Test stat| > critical value
Decision: Reject H0
d) If appropriate, compute the CI. If not
appropriate, input "na" for both spaces below.
95% confidence interval for difference between the population mean is given by
We have all the values we need
(-6.4517,-0.4372)
e) Compute the corresponding effect size(s) and
indicate magnitude(s).
Effect size =
=
Effect size = 1.1446 we take the absolute
value
since effect size > 0.8
Large effect
f) Make an interpretation based on the
results.
Well since the ratings were more for physical guidence we can say that
a. Self-care skills improve when learned through physical guidance.
Although for checking this we need to conduct a 1-tailed test.
c. There is no significant self-care difference between video imitation and physical guidance.
No significance is when we do not rejec the hypothesis.