Casio fx-50F –4209356544, Number, Weight, of Days, Operation Procedure, 1 Linear Regression, Logarithmic Regression, 20,3150, 50,4800, 80,6420, 110,7310, 140,7940

Example 2: The nearby data shows how the weight of a newborn at various numbers of days after birth.

1 Obtain the regression formula and correlation coefficient produced by linear regression of the data.

2 Obtain the regression formula and correlation coefficient produced by logarithmic regression of the data.

3 Predict the weight 350 days after birth based on the regression formula that best fits the trend of the data in accordance with the regression results.

Operation Procedure

Enter the REG Mode and select linear regression:

Number	Weight
of Days	(g)
20	3150
50	4800
80	6420
110	7310
140	7940
170	8690
200	8800
230	9130
260	9270
290	9310
320	9390

N5(REG)1(Lin)Select FreqOff for the statistical frequency setting: 1N(SETUP)dd2(FreqOff)

Input the sample data: 20,3150m(DT)50,4800m(DT) 80,6420m(DT)110,7310m(DT) 140,7940m(DT)170,8690m(DT) 200,8800m(DT)230,9130m(DT) 260,9270m(DT)290,9310m(DT) 320,9390m(DT)

1 Linear Regression

Regression Formula Contant Term a: 12(S-VAR)1(VAR)ee1(a)E

a

4446575758

Regression Coefficient b:12(S-VAR)1(VAR)ee2(b)E

b

1887575758

Correlation Coefficient:12(S-VAR)1(VAR)ee3(r)E

r

0904793561

2 Logarithmic Regression Select logarithmic regression:

12(S-VAR)3(TYPE)2(Log)	x1 =
	20

Regression Formula Contant Term a: A12(S-VAR)1(VAR)ee1(a)E

a

–4209356544

E-51