UNIT 2 VOCAB

Scatterplot

A plot of paired measurements on a collection of individuals

Positive Association

An association between 2 variables - where as one variable increases - so does the other

Negative Association

An association between 2 variables - where as one variable increases - the other decreases

Strong Association

An association where the data points fall close to a line

True/False: Correlation implies causation

False

True/False: If the correlation coefficient is 1, then the slope must be 1 as well.

False

True/False: If there is an association identified between the explanatory and response variable, the relationship is causal.

False

True/False: The response variable is always caused by the explanatory variable

False

True/False: When ice cream sales go up, so do crime rates. A reasonable conclusion is that the increase in ice cream sales causes an increase in the crime rate.

False

Strength

How well the association follows the form

Response Variable

The dependent variable (y) in a linear regression

Explanatory Variable

The independent variable (x) in a linear regression

Form

The type of association - linear or other

True/False: Association does not imply causation.

True

True/False: Correlation coefficient and the slope always have the same sign (positive or negative).

True

True/False: Correlation measures the strength of linear association between two numerical variables.

True

True/False: If the correlation between two variables is close to 0.01, then there is a very weak linear relation between them.

True

True/False: When ice cream sales go up, so do crime rates. A reasonable conclusion is that there is an association between ice cream sales and the crime rate.

True

Linear Association

Two variables, where as one variable increases by a unit - the other variable changes by a constant amount

Direction

Whether the association is increasing or decreasing

Context

Who-What-Where-When-Why