Correlation and regression

Question 1

correlation

Answer 1

relationship between 2 continuous variable. Quantifies the co-relationship b/w 2 variable

Question 2

person’s correlation coefficient, rho or p

Answer 2

this takes numbers between 1 + -1

1= v strong correlation
0= no correlation
-1=negative correlation

Question 3

correlation p value

Answer 3

direct correlation between correlation and p-value. Graphical method used . As the sample size increases the probability of a strong correlation increases.

Question 4

assumptions of correlation analysis

Answer 4

• data points are independent
• one set of data is normally distributed for any given value of the other with constant variance
• linear relationship

Question 5

use spearmans rank if..

Answer 5

later 2 assumptions don’t apply

Question 6

spearmint rank

Answer 6

simply replaces values with their rank before calculated correlation coefficient

Question 7

regression

Answer 7

used to look at the relationship between 2 continuous variables. rather than quantity a strength of association it fits a functional form

Question 8

functional form of regression

Answer 8

y=bx + c

y= outcome (dependent variable)
b= slope- average change in y per unit change in x
x= independent variable
c= intercept- when x=0

Question 9

Regression squared=

Answer 9

the square root of persons correlation

Question 10

assumptions of regression

Answer 10

• data points are independent
• outcome data is normally distributed for any given value of the independent
• dependent data has a constant variance for all values of the independent data
• linear relationship