Sharp EL-9650

172
CHAPTER 7
for US
2. Regression
• Regression curves are selected from the [D REG] menu in the statistic mode.
• Check the menu contents.
Press
D to display the primary screen of the REG menu. There are two
other screens that can be accessed by moving the cursor pointer to the submenu
side (the right half of the screen displaying “01 Med_Med”, etc.) and pressing Å
≥ Å ≥.
Primary screen Secondary screen Third screen
Function name Description Regression formula Parameter
01 Med_Med Finds the regression curve
using the median-median
method.
02 Rg_ax+b Finds the regression curve
using the linear equation
(linear regression-1).
03 Rg_a+bx Finds the regression curve
using the linear equation
(linear regression-2).
04 Rg_x
2
Finds the regression curve
using the second degree
polynomial (quadratic
regression).
05 Rg_x
3
Finds the regression curve
using the third degree
polynomial (cubic regres-
sion).
06 Rg_x
4
Finds the regression curve
using the fourth degree
polynomial (quartic regres-
sion).
y=ax+b a,b
y=ax+b a, b, r, r
2
y=a+bx a, b, r, r
2
y=ax
2
+bx+c a, b, c, R
2
y=ax
3
+bx
2
+cx+d a, b, c, d, R
2
y=ax
4
+bx
3
+cx
2
+dx+e a, b, c, d, e, R
2
EL-9650-(07)En (157-177) 8/1/00, 9:06 AM172