User`s guide

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Chapter 7 Statistical Graphs and Calculations

4. Calculating and Graphing Paired-

Variable Statistical Data

Under “Plotting a Scatter Diagram,” we displayed a scatter diagram and then per-

formed a logarithmic regression calculation. Let’s use the same procedure to look at

the six regression functions.

k Linear Regression Graph

Linear regression plots a straight line that passes close to as many data points as

possible, and returns values for the slope and y-intercept (y-coordinate when x = 0)

of the line.

The graphic representation of this relationship is a linear regression graph.

Q1(GRPH)[4(SET)c

1(Scat)

Q1(GRPH)1(GPH1)

1(X)

4(DRAW)

The following are the meanings of the above parameters.

a ...... Regression coefficient (slope)

b ...... Regression constant term (y-intercept)

r ...... Correlation coefficient

(G-Type)

(Scat)

(GPH1)

(X)

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