Unit 2

Question 1

birative data

Answer 1

comparing two sets of data

Question 2

explanatory variable

Answer 2

the independent variable or the variable that impacts the other variable; resides on the x axis

Question 3

response variable

Answer 3

the dependent variable or the variable that is impacted by the other variable; resides on the y axis

Question 4

correlation coefficient

Answer 4

a number between -1 to 1 that tells us the strength and direction of a relationship. It can be represented by the equation (zx*zy)/n-1

Question 5

Least Squares Regression Line

Answer 5

best fit line for the scatterplot; represented by y=mx+b

Question 6

sum of squared errors

Answer 6

its another way to see how far the points are from the line; the smaller the residual, the better fit line

Question 7

residual or error

Answer 7

observed - predicted

Question 8

extrapolation

Answer 8

when the data is outside of the domain

Question 9

lurking variable

Answer 9

a hidden variable that could be impacting both the explanatory and response variables

Question 10

leverage

Answer 10

points extraordinary in x

Question 11

influential point

Answer 11

a term to name if an outlier or leverage point has the potential to change the slope or lsrl if removed

Question 12

coefficient of determination (R^2)

Answer 12

the percent of variability in the y variable can be explained by x variable

Question 13

regression to the mean

Answer 13

the tendency for extreme occurances to be more average in the future

Question 14

scatterplot

Answer 14

a method of representing data between two variables

Question 15

DOFS

Answer 15

(Direction, Outliers, Form, Strength)

Question 16

Residual Standard Deviation

Answer 16

measures how much the points spread around the LSRL

Question 17

Re-Expressing

Answer 17

make the form of a scatterplot more nearly linear by taking the square root or log of y (sometimes the x variable too)