correlation and association

Question 1

what is correlation?

Answer 1

the linear relationship between 2 continuous variable

Question 2

what is association?

Answer 2

the rs between 2 categorical variables

Question 3

what tests should you use for correlation?

Answer 3

pearson’s correlation
spearman’s rank correlation

Question 4

what test should you use for association?

Answer 4

Pearson’s chi square for independence

Question 5

what is Pearson’s correlation denoted by?

Answer 5

p or r

Question 6

what is the range for pearson’s correlation?

Answer 6

-1 to 1

Question 7

what does p = 1 for pearson’s correlation

Answer 7

perfectly positive linear rs between X and Y

Question 8

what does p = -1 for pearson’s correlation

Answer 8

perfectly negative linear rs between X and Y

Question 9

how will pearson’s correlation results be displayed?

Answer 9

on a scatterplot

Question 10

what type of data is applicable for pearson’s correlation test?

Answer 10

interval/ratio scale

Question 11

does pearson’s correlation require normal distribution?

Answer 11

yes

Question 12

is pearson’s correlation parametric or non parametric?

Answer 12

parametric

Question 13

what are the values for pearson’s correlation test? strong moderate weak

Answer 13

strong: r>0.7 OR r<-0.7
moderate: 0.3< r <- 0.7
weak: 0.3 >-r >- -0.3

Question 14

what is regression

Answer 14

to examine the linear rs between X and the mean of Y

Question 15

is spearman’s rank correlation coefficient parametric or non para metric?

Answer 15

non parametric

Question 16

what does the spearman’s rank correlation coefficient measure?

Answer 16

monotonic function

Question 17

what is the range for spearman’s rank correlation coefficient

Answer 17

-1 to 1

Question 18

what does -1 for spearman’s rank correlation coefficient mean?

Answer 18

perfectly monotonic negative

Question 19

what does 1 for spearman’s rank correlation coefficient mean?

Answer 19

perfectly monotonic positive

Question 20

what does monotonic rs mean?

Answer 20

either
- when X increase, Y increases too

OR

• when X increases, Y decreases.

it happens NOT at a constant rate

Question 21

what is pearson’s chi square for independence for ?

Answer 21

to test whether there is a significant association between 2 categorical variables

Question 22

list the test to check for association

Answer 22

pearson’s chi square for independence

Question 23

what type of data does the pearson’s chi square test ?

Answer 23

nominal or ordinal

Question 24

can pearson’s chi square of independence be used for continuous variables?

Answer 24

no

Question 25

does pearson’s chi square measure the direction or strength of a relationship

Answer 25

nO ONLY association.