Statistics Test 2 Johnson

r^2

Coefficient of Determination

r

Correlation Coefficient

...the line is a perfect positively sloped line.

If the r value is 1 then...

...the line is a perfect negatively sloped line.

If the r value is -1 then...

LinReg(ax+b) or LinReg(a+bx)

LSRL / Least Square Regression Line

The difference between an actual value ( y ) and a predicted value ( y hat ). (y) - (y hat)

Residual

Located below the LSRL

Negative Residual

Located above the LSRL

Positive Residual

Must be interpreted to help confirm a linear relationship.

Residual Plot

Must have a "good" r value and a "good" residual plot

Linear Relationship

Use technology or formulas for slope and y intercept from your formula sheet

Finding the LSRL

Minimizes the sum of the areas formed by squaring the residuals.

Concept of the LSRL

In bi-variate data, drastically changes the r value, slope, and y intercept

Influential Point

Used to find a z score or location

invNorm

Used to find an area / probability

normalcdf

...always located on the LSRL.

The coordinate x bar, y bar is ...