Owner's manual

Page 18-11

Θ First, enter the two rows of data into column in the variable ΣDAT by using

the matrix writer, and function STOΣ.

Θ To access the program

3. Fit data.., use the following keystrokes:

‚Ù˜˜@@@OK@@@ The input form will show the current ΣDAT, already

loaded. If needed, change your set up screen to the following parameters

for a linear fitting:

Θ To obtain the data fitting press @@OK@@. The output from this program, shown

below for our particular data set, consists of the following three lines in RPN

mode:

3: '0.195238095238 + 2.00857142857*X'

2: Correlation: 0.983781424465

1: Covariance: 7.03

Level 3 shows the form of the equation. In this case, y = 0.06924 + 0.00383 x.

Level 2 shows the sample correlation coefficient, and level 1 shows the

covariance of x-y.

Definitions

For a sample of data points (x,y), we define the sample covariance as

The sample correlation coefficient for x,y is defined as

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ixy

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