In: Statistics and Probability
Administrators are sure about the effectiveness of the Apple
Orchard Preschool spelling program. The average spelling score is
25 for children of comparative age. The data below are spelling
scores from a sample of children from Apple Orchard Preschool.
Scores range from 0 - 40 with higher scores indicating better
spelling. What can be concluded with an α of 0.05?
id | spelling |
35 36 37 38 39 40 41 42 43 44 45 10 11 12 13 14 15 16 17 18 |
27 33 38 23 19 27 29 18 21 35 18 28 23 22 24 20 35 24 17 16 |
a) What is the appropriate test statistic?
---Select---
Options are: na, z-test, One-Sample t-test, Independent-Samples
t-test, or Related-Samples t-test
b)
Population:
---Select---
-Options are: Apple Orchard Preschool, spelling, children of comparative age, spelling scores, or Administrators
Sample:
---Select---
-Options are: Apple Orchard Preschool, spelling, children of comparative age, spelling scores, or Administrators
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: ---Select---
Options are: Reject H0 Fail or 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 =_____ ; ---Select---
-Options are: na, trivial effect, small effect, medium effect, or large effect
r2 = _____ ; ---Select---
-Options are: na, trivial effect, small effect, medium effect, or large effect
e) Make an interpretation based on the results.
Which one is correct?
a)Apple Orchard Preschool has a significantly effective spelling program.
b)Apple Orchard Preschool has a significantly ineffective spelling program.
c)Apple Orchard Preschool spelling program does not have a significant effect.
Solution:
a)The appropriate test statistic is one sample t-test. Since n< 30, we use t- test.
b)Population: Apple Orchard Preschool children
Sample: Children of comparative age
c) The following table shows the T test result from excel.
t-Test: One sample t test | |
spelling | |
Mean | 24.85 |
Variance | 42.34473684 |
Observations | 20 |
Hypothesized Mean Difference | 25 |
df | 19 |
t Stat | -0.103087626 |
P(T<=t) one-tail | 0.459486863 |
t Critical one-tail | 1.729132812 |
P(T<=t) two-tail | 0.918973726 |
t Critical two-tail | 2.093024054 |
Hypothesis:
Null Hypothesis H0: =25
Alternative Hypothesis H1: 25
P value from the above table= 0.918973726
Since t Stat=-0.103087626 which is less than t Critical value=2.093024054, we accept the null hypothesis and conclude =25.
e) a)Apple Orchard Preschool has a significantly effective spelling program.