Unit 9- Scatter Plots and Data

Outliers

a point that does not fit the overall pattern or trend of a scatter plot

Non-Linear Association

association that can NOT be represented with a straight line

Linear Association

association that can be represented with a straight line

Categorical Data

data that consists of names, labels, or other nonnumerical values

Bivariate Data

data with two variables

Scatter Plot

graphs that use points to display numerical data with two variables.

Strong Association

if the points of data are close together

Weak Association

if the points of data are widely spread out

Frequency

number of times, something occurs

Association

overall trends, or patterns

Relative Frequency

tells us the number of times something occurs compared to the total - usually expressed as a percentage

Negative Association

variables move in opposite directions - as one variable increases, the other variable decreases, or vice versa

Positive Association

variables move together - as one variable increases, the other variable increases or as one variable decreases, the other variable decreases

Trend Lines

when scatterplots demonstrate a linear relationship, a straight line can be used to show the general pattern of the data - also known as a line of best fit - should be as close as possible to the points of data in a scatter plot

No Association

when the change in one variable has no effect on the second variable

Clustering

when there are distinct or separate groups of points in a scatter plot