PSY 3200
Unit #2 AS: Calculating Central Tendency, Variability and Sampling
In this experiment you will demonstrate your ability to calculate the Measures of Central tendency and Variability. You will also identify types of sampling.
In part 1 of this assignment you will be given 3 sets of data. You will calculate (1) mean, (2) median, (3) mode, (4) range, (5) variance, and (6) standard deviation for each set of data. Be sure to type out any work if needed.
In part 2 you will be given two experimental scenarios, you will need to identify the type of sampling that was used and whether or not random assignment was used. You will also need to explain the rationale for your answer. These answers will be filled out in the provided word document and submitted via blackboard.
Part 1
For the following three data sets, calculate the:
a. mean (3 pts)
b. median (2 pts)
c. mode (1 pt)
d. range (2 pts)
e. variance (5 pts)
f. standard deviation (2 pts)
Data Set 1:
3, 4, 2, 2, 3, 4, 2, 1, 9, 6, 2, 5, 6, 3, 2, 4, 2
Data Set 2:
23, 22, 21, 22, 22, 22, 21, 23, 25, 23, 22, 23, 24, 25, 25, 21
Data Set 3:
13, 18, 34, 1, 18, 63, 34, 31, 10, 4, 123
Part 2
For the following experiments indicate:
a. what type of sampling was used [cluster, stratified, convenience, or volunteer]? (2 pts)
b. what is your rationale for that type of sampling? (3 pts)
c. was random assignment used? (2 pts)
d. what is your rationale for choosing whether or not random assignment was used? (3 pts)
Experiment 1:
A social psychologist is interested in whether married people report greater levels of happiness than non-married people. She puts an ad in a local newspaper. The ads says that she is seeking volunteers for a study on happiness, and that she is looking for married people and non-married people to participate. She pays participants $5 each. She has them answer a series about their happiness. Her data show that married people, on average, had higher happiness scores than non-married people.
Experiment 2:
A social psychologist conducts a study to examine whether watching aggressive TV shows causes aggressive behavior. He randomly assigns all 10 yr-old boys in a rich, suburban neighborhood to one of two groups: one group watches one hour of a violent TV show, and the other group watchers 1 hour of a non-violent TV show. After the children watch the TV program, they are sent off to the playground. The researcher videotapes the playground interactions and counts the number of hits and kicks from each child. The researcher finds that kids who watched the violent TV show were more aggressive than kids who watched the non-violent TV show.
