Grouped Standard Deviation - HP 33s User Manual

¥
55
¥
15.3
t
D
¥
90
Thus, we would expect that only about 1 percent of the students would do better
than score 90.
Keys:
(In RPN mode)
t
I
¥
0.1
¥
¥
0.8

Grouped Standard Deviation

The standard deviation of grouped data, S
points x , x , ... , x
1 2
This program allows you to input data, correct entries, and calculate the standard
deviation and weighted mean of the grouped data.




value 


Display:








, occurring at positive integer frequencies f
n
∑
x
S
xg
Stores 55 for the mean.
Stores 15.3 for the standard
deviation.
Starts the distribution program and
prompts for X .
Enters 90 for X and calculates Q ( X ).
Description:
Starts the inverse routine.
Stores 0.1 (10 percent) in Q ( X ) and
calculates X .
Resumes the inverse routine.
Stores 0.8 (100 percent minus 20
percent) in Q ( X ) and calculates X .
, is the standard deviation of data
xy
∑
( x ) f
2
2
i i
f
∑
i i
f
i
∑
( ) f 1
i
Statistics Programs
, f , ... , f .
1 2 n
16–17