Sharp PC-1403 - Page 45

39
P r ed ic t t h e ag e o f dea t h of a 6 - foot man w e i gh i ng 190 po und s in 1 950 .
190 I s H1FT I rTI 73 .4 94 5 283 ye a r s
T o rea c h ag e 9 0 , wh a t sho ul d a m an ' s weight be i n 1 9 60 ?
90 l s tt1 F T ) [E) 1 6 0 . 371 2 10 8 p ound s
To rea c h age 1 5 0, w h a t s hould a m an ' s weight be ? Ob viou s l y , the an swe r will m a ke
no sen s e, indi cat in g t he d anger of c a rrying a str ai gh t -line e x t r apolation t oo fa r .
32 1 . 9 29 2 125 ( y- ax i s)
- 1.7 95 0 88908 ( s lo p e )
!SHIFT ) m
I S H I FT ) W
- 0 . 79 29 26 1 6 7
2 .
1 .
D i sp la y
0 .
! SH IFT ) ~
72 M 185 ~
67 @ 226 ~
(Co nt i nu e to pl ac e in a ll data)
l s HIFT I [r)
T he v a l ue fo r r indi c ates a r ela tive l y high negati v e c o r relation . A h i gher we ight mean s a
sho rter li te s pan . To g raph t he regression l ine , co e ff i c i e nt s a and b a r e u sed .
W e i gh tat ag e65 18 5 226 2 00 1 6 9 170 195 1 75 174 198 172
9 10 7 8
5 6 4 3
2
S am p le
7 2 67 6 9 85 9 1 68 77 74 70 82
Age at dea th
Ex a m pl e 2 : I s w e i g ht a go od p r ed ic t o r of longe vi t y among m e n 6 5 y e ars o f a ge ? I n
195 0, 10 m en , each s i x f eet tall, wer e se l ec t e d for a n e x perim e n t t o
de t er mine i f th eir weight eff ec t ed their life s pan .
If w e h a d a s t u de nt w h ose m ar k in ma th e m at i cs wa s 90 , t he student wo u l d ha ve a ma r k
o f 95 i n Eng l ish b as ed o n thi s ana l ysis .
Displ a y
9 5 . 33333333
K e y in :
90 I SHI FT I [El
T h e val u e o f 0 . 5 71 5 8 790 1 for r i ndicates tha t t h e co r rel at i o n i s m ode ra te . T he
e qu at io n f o r t h e s tr a ight lin e for this d a ta i s y = 34 : 26 + 0 . 68x w h e n t r u nc at ed to
s eco nd de c i ma l pl ac e s .
0 . 5 7 1587901
34 .26 190 4 7 6 (y - a x i s)
0 .67 8 57142 8 (slop e )
I SHIFT ! [TI
I S HIFT I [~ Cl
! SH IFT! m
Using as a Calculator