HP 33s User Manual
Page 280
16–20
Statistics Programs
Program Instructions:
1.
Key in the program routines; press
when done.
2.
Press
X
S to start entering new data.
3.
Key
in
x
i
–value (data point) and press
g
.
4.
Key
in
f
i
–value (frequency) and press
g
.
5.
Press
g
after VIEWing the number of points entered.
6.
Repeat steps 3 through 5 for each data point.
If you discover that you have made a data-entry error (x
i
or f
i
) after you have
pressed
g
in step 4, press
X
U and then press
g
again. Then go
back to step 3 to enter the correct data.
7.
When the last data pair has been input, press
X
G to calculate and
display the grouped standard deviation.
8.
Press
g
to display the weighted mean of the grouped data.
9.
To add additional data points, press
g
and continue at step 3.
To start a new problem, start at step 2.
Variables Used:
X
Data point.
F
Data–point frequency.
N
Data–pair counter.
S
Grouped standard deviation.
M
Weighted mean.
i
Index variable used to indirectly address the correct
statistics register.
Register 28
Summation
Σf
i
.
Register 29
Summation
Σx
i
f
i
.
Register 31
Summation
Σx
i2
f
i
.
Example:
Enter the following data and calculate the grouped standard deviation.