EASTERN MEDITERRANEAN UNIVERSITY SPRING 2013-PSYC216 LAB ACTIVITY 1

EASTERN MEDITERRANEAN UNIVERSITY
SPRING 2013-PSYC216
LAB ACTIVITY 1
Dr. Mevhibe B. Hocaoglu OFFICE: AS311 OFFICE PHONE: 630 1283
E-MAIL: mevhibe.hocaoglu@emu.edu.tr
STUDENT SURNAME:
STUDENT NUMBER:
1. One sample has n=15 with SS=1660 and a second sample has n=15 with SS=1700.
a. Find the pooled variance for the two samples.
b. What is the estimated standard error for the sample mean difference?
c. If the sample mean difference is 8, can we reject the H0 at 0.05 significance level?
d. If the sample mean difference is 12, can we reject the H0 at 0.05 significance level?
e. Calculate the effect size for 8 mean difference.
2.
A researcher is interested in evaluating the difference in mathematical skills of 8-year old boys and 8-year old
girls. A sample size of n=5 girls and n=5 boys complete a math test. The chart below shows the results:
GIRLS
M=83
SS=200
BOYS
M=71
SS=120
Carry out a hypothesis test to see if there is any significant difference between 8-year old boys and girls
in mathematical skills at p=0.05 level of significance (α=0.05).
3.
Elderly people who own pets visit their doctors less. A study was carried out to test this hypothesis.
The following data were collected on the number of visits that a control group (no-dogs) and dog
owners paid to the their doctors in the past year.
Control Group
12
10
6
9
15
12
14
a.
Dog Owners
8
5
9
4
6
Is there a significant difference between the number of visits to doctors between dog owners
and the control group? (two tailed test at α=0.05)
b. Calculate the effect size (r2) for the data.