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HP 30b Business Professional Calculator User Manual

Page 79

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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