Chapter 7

Question 1

scatterplot

Answer 1

shows the relationship between two quantitative variables measures on the same cases.

Question 2

Association

Answer 2

Direction- A positive direction or association means that in general, as one variable increases, so does the other, the association is negative.
Form-the form we care about most is straight, but you should certainly describe other patterns you see in scatter plots.
Strength- a scatter plot is said to show a strong association if there is litter scatter around the underlying relationship.

Question 3

Response Variable
explanatory variable
x- variable
y-variable

Answer 3

in a scatter plot,you must choose a role for each variable. assign to the y-axis the response variable that you hope to predict or explain. Assign to the x-axis the explanatory or predictor variable that accounts for, explains, predicts or is otherwise responsible for the y- variable

Question 4

correlation ceofficient

Answer 4

the correlation coefficient is a numerical measure of the direction and strength of a linear association.