Hp 49g+ User Manual download pdf (Page 578)

• 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.

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

The sample correlation coefficient for x,y is defined as

are the standard deviations of x and y, respectively, i.e.

The values s

are the "Covariance" and "Correlation," respectively,

obtained by using the "Fit data" feature of the calculator.

Linearized relationships

Many curvilinear relationships "straighten out" to a linear form. For example,

the different models for data fitting provided by the calculator can be

linearized as described in the table below.

Hp 49g+ User Manual Page 578