PSYC 2317 SOLUTIONS
PSYC 2317
Assignment #1Define the terms population, sample, parameter, and statistic, and explain how
1.1 these terms are related to each other (describe in your own words).
Define in your own words the concept of sampling error. Be sure that your
1.2 definition includes the concepts of statistic and parameter. What impact could sampling error have on a research study?
A researcher would like to evaluate the claim that drinking large quantities of
1.3 water can help prevent the common cold. One group of participants drinks 8 glasses of water every day, and a second group drinks 2 glasses of water every day. The researcher records the number of colds each individual experiences during the 4-month winter season.
Identify the dependent variable for this study.
Is the dependent variable discrete or continuous?
What scale of measurement (nominal, ordinal, or interval/ratio) is used to measure the dependent variable?
What is the independent variable?
What research method is being used (experimental or correlational?
1.4 For the following set of scores (9, 2, 3, 5), find the value of each expression:
X2
(X)2
(X - 4)
(X – 4)2
Make a table to show your calculations for each expression above, as I show you to do on the Tips and Hints class video and handout. Assume the data below is a sample group of 4 persons. Each person's score is listed below: X
9
2
3
5 X =
X, Y variables
n number of people in a research group or sample
N number of people in target population
ρ rho (pronounced row)
Σ sum (sigma)
μ populational mean (pronounced mu)
M sample mean (pronounced x bar)
α alpha
β beta
≥ greater than or equal to
≤ less than or equal to
σ populational standard deviation (sigma)
s sample standard deviation (also will see the symbol, SD)
± plus/minus
Order of Mathematical OperationsParentheses (innermost to outermost)
Exponents
Multiplying/dividing
Summation (Σ)
Adding/subtracting
Example: 3(X2-2XY)(2+7X2+X)2+2 What order would you do the calculations? (X-Y)(Y-X2) If x = 2 & y = 3
