27.03.2013 Views

SPSS® 12.0 Command Syntax Reference

SPSS® 12.0 Command Syntax Reference

SPSS® 12.0 Command Syntax Reference

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

762 IGRAPH<br />

HISTOGRAM Subcommand<br />

HISTOGRAM creates a histogram element in a chart, corresponding to the X1, X2, and Y axis<br />

assignments. Horizontal or vertical orientation is specified by the COORDINATE subcommand.<br />

A histogram groups the values of a variable into evenly spaced groups (intervals or<br />

bins) and plots a count of the number of cases in each group. The count can be expressed as<br />

a percentage. Percentages are useful for comparing data sets of different sizes. The count or<br />

percentage can also be accumulated across the groups.<br />

• $COUNT or $PCT must be specified on the Y subcommand.<br />

The following keywords are available:<br />

SHAPE Defines the shape of the histogram. Currently, the only value for<br />

SHAPE is HISTOGRAM.<br />

CUM Specifies a cumulative histogram. Counts or percentages are aggregated<br />

across the values of the domain variables.<br />

X1INTERVAL Intervals on the X1 axis can be set automatically, or you can specify<br />

the number of intervals (1 to 250) along the axis (NUM) or the width<br />

of an interval (WIDTH).<br />

X2INTERVAL Intervals on the X2 axis can be set automatically, or you can specify<br />

the number of intervals (1 to 250) along the axis (NUM) or the width<br />

of an interval (WIDTH).<br />

CURVE Superimposes a normal curve on a 2-D histogram. The normal curve<br />

has the same mean and variance as the data.<br />

X1START The starting point along the X1 axis. Indicates the percentage of an<br />

interval width above the minimum value along the X1 axis at which to<br />

begin the histogram. The value can range from 0 to 99.<br />

X2START The starting point along the X2 axis. Indicates the percentage of an<br />

interval width above the minimum value along the X2 axis at which to<br />

begin the histogram. The value can range from 0 to 99.<br />

Example<br />

IGRAPH<br />

/X1=VAR(sales96) TYPE=SCALE<br />

/Y=$count<br />

/Histogram SHAPE=HISTOGRAM CURVE=ON X1INTERVAL WIDTH=100.<br />

• Histogram creates a histogram of sales96. The sales96 intervals are 100 units wide.<br />

• CURVE superimposes a normal curve on the histogram.<br />

FITLINE Subcommand<br />

FITLINE adds a line or surface to a scatterplot to help you discern the relationship shown in<br />

the plot. The following general methods are available:<br />

NONE No line is fit.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!