Correlation: Chapter 12

Question 1

goal of correlational research

Answer 1

• establish that a relation/association exists between variables
• describe the nature of the relationship

Question 2

manipulation and control of variables

Answer 2

no attempt to manipulate, control, or interfere with the variables

Question 3

correlational data presentation

Answer 3

• each individual = two data points (one for each
  variable)
• data = presented in a table
• data points can be presented on a scatterplot

Question 4

characteristics of the correlation

Answer 4

• form
• direction
• strength

Question 5

form of the correlation

Answer 5

looking for pattern in data suggesting consistent and predictable relationship
* Linear relationship
* Non-Linear relationship

Question 6

direction of the correlation

Answer 6

positive correlation (+)
- increases in 𝑥 are paired with increases in 𝑦
negative correlation (-)
- increases in 𝑥 are paired with decreases in 𝑦

Question 7

strength of correlation

Answer 7

• degree of association between 2 variables
• expressed mathematically as the correlation
  coefficient (r)
• when the two variables are either ratio or
  interval, we use Pearson r

Question 8

strength of correlation (r)

Answer 8

• 𝑟 near 0 indicate weak relations
• 𝑟 close to -1 or 1 indicate that points lie close to
  a straight line
• 𝑟 equal to -1 or 1 indicate that points lie exactly
  along a straight line

Question 9

the regression line

Answer 9

• line is drawn through the points
• the closer the points are to the line, the greater the association between the variables

Question 10

shared variance

Answer 10

• shared common ground between variables A + B
• r^2 = coefficient of determination = shared variance

Question 11

correlational variables are ___

Answer 11

ordinal (not equal increments)

Question 12

correlation matrix

Answer 12

refer to powerpoint on chapter 12, slide 25

Question 13

correlation is not ___

Answer 13

causation

Question 14

third variable problem (spurious correlation)

Answer 14

a third variable can cause A and B

Question 15

directionality

Answer 15

correlating can suggest a direction
ex:
higher social media use causes depression
vs
depression causes higher social media use

Question 16

correlations are useful for ___

Answer 16

predictions

Question 17

regression analysis usage

Answer 17

• way of using associations between variables as a method of prediction
• predictor variable (IV)
• criterion variable (DV)

Question 18

predictor variable

Answer 18

predicts y

Question 19

criterion variable

Answer 19

y

Question 20

reliability and validity

Answer 20

correlations can be used to determine reliability and validity
- test-retest reliability
- concurrent validity

Question 21

evaluating theories

Answer 21

correlations can be used to evaluate theories

Question 22

potential problems for pearson r

Answer 22

• correlation has to be linear
• when range of values measured for one of the variables is restricted; leads to misleading results.

Question 23

correlation strengths

Answer 23

• can investigate unethical hypotheses
• helps identify where to look for causes
• high external validity
• record what exists naturally

Question 24

correlation weaknesses

Answer 24

• cannot assess causality
• low internal validity