HP 30b - Business Professional Calculator - Page 79

Statistical Operations
71
*Does not apply to the HP 20b.
y Std. Dev Standard deviation for y: a measure of how dispersed the y data values are about
the mean.
x Population Dev Population Standard deviation for x: a measure of how dispersed the x data values
are about the mean, assuming the data constitutes a complete set of data.
y Population Dev Population Standard deviation for y: a measure of how dispersed the y data values
are about the mean, assuming the data constitutes a complete set of data.
S.E.Samp.
x Standard error for the sample x: a measure of the dispersion of x mean, assuming
the data is a sampling of a large, more complete data set.
S.E.Samp.
y Standard error for the sample y: a measure of the dispersion of y mean, assuming
the data is a sampling of a large, more complete data set.
Pred
x Predicts x for a given hypothetical value of y, based upon the model calculated to fit
the data.
Pred
y
Predicts y for a given hypothetical value of x, based upon the model calculated to fit
the data.
a The a coefficient for the chosen regression model, which is the slope for a linear
model.
b The b coefficient for the chosen regression model, which is the y-intercept for a linear
model.
c
The c coefficient for the chosen regression model, applies only for ax
2
+bx+c.
Correlation
The correlation coefficient for the given (
x, y) data. The correlation coefficient is a
number in the range -1 through 1 that measures how closely the calculated line fits
the data.
Covariance A measure of how much two variables change in relation to one another.
The sum of the
x values.
The sum of the
y values.
The sum of the squares of the
x values.
The sum of the squares for the
y values.
The sum of the products of the
x and y values.
Quartiles* The boundaries of a given frequency distribution divided into four parts.
Median* The middle value in a given frequency distribution.
Maximum* The largest value in a given frequency distribution.
Minimum* The lowest value in a given frequency distribution.
Table 12-1 The Statistics Menu Items
Menu Item Description
Σx
Σy
Σx
2
Σy
2
Σxy