measurements of a sample of healthy adults selected at random.
However, the data entry clerk made a number of mistakes when entering
the data.
-@ref{descriptives} illustrates the use of @cmd{DESCRIPTIVES} to screen this
+@ref{ex-descriptives} illustrates the use of @cmd{DESCRIPTIVES} to screen this
data and identify the erroneous values.
-@float Example, descriptives
+@float Example, ex-descriptives
@cartouche
@example
@prompt{PSPP>} get file='@value{example-dir}/physiology.sav'.
column, suggesting incorrect data entry.}
@end float
-In the output of @ref{descriptives},
+In the output of @ref{ex-descriptives},
the most interesting column is the minimum value.
The @var{weight} variable has a minimum value of less than zero,
which is clearly erroneous.
@float Example, ex1
@cartouche
-[@dots{} continue from @ref{descriptives}]
+[@dots{} continue from @ref{ex-descriptives}]
@example
@prompt{PSPP>} examine height, weight /statistics=extreme(3).
@end example
For detailed information about the @cmd{RECODE} command @pxref{RECODE}.
If you now re-run the @cmd{DESCRIPTIVES} or @cmd{EXAMINE} commands in
-@ref{descriptives} and @ref{ex1} you
+@ref{ex-descriptives} and @ref{ex1} you
will see a data summary with more plausible parameters.
You will also notice that the data summaries indicate the two missing values.
Data entry errors are not the only reason for wanting to recode data.
The sample file @file{hotel.sav} comprises data gathered from a
customer satisfaction survey of clients at a particular hotel.
-In @ref{reliability}, this file is loaded for analysis.
+In @ref{ex-reliability}, this file is loaded for analysis.
The line @code{display dictionary.} tells @pspp{} to display the
variables and associated data.
The output from this command has been omitted from the example for the sake of clarity, but
compute @var{var} = 6 - @var{var}.
@end example
@noindent
-@ref{reliability} uses this technique to recode the variables
+@ref{ex-reliability} uses this technique to recode the variables
@var{v3} and @var{v5}.
After applying @cmd{COMPUTE} for both variables,
all subsequent commands will use the inverted values.
One would therefore expect the values of these variables (after recoding)
to closely follow one another, and we can test that with the @cmd{RELIABILITY}
command (@pxref{RELIABILITY}).
-@ref{reliability} shows a @pspp{} session where the user (after recoding
+@ref{ex-reliability} shows a @pspp{} session where the user (after recoding
negatively scaled variables) requests reliability statistics for
@var{v1}, @var{v3} and @var{v4}.
-@float Example, reliability
+@float Example, ex-reliability
@cartouche
@example
@prompt{PSPP>} get file='@value{example-dir}/hotel.sav'.
The @cmd{T-TEST} command is used to find out whether or not two separate
subsets have the same mean.
-@ref{t-test} uses the file @file{physiology.sav} previously
+@ref{ex-t-test} uses the file @file{physiology.sav} previously
encountered.
A researcher suspected that the heights and core body
temperature of persons might be different depending upon their sex.
the null hypothesis and conclude that there is insufficient evidence to
suggest that the body temperature of male and female persons are different.
-@float Example, t-test
+@float Example, ex-t-test
@cartouche
@example
@prompt{PSPP>} get file='@value{example-dir}/physiology.sav'.
If a variable is found to be linearly related, then this can be used to
predict future values of that variable.
-In example @ref{regression}, the service department of the company wanted to
+In example @ref{ex-regression}, the service department of the company wanted to
be able to predict the time to repair equipment, in order to improve
the accuracy of their quotations.
It was suggested that the time to repair might be related to the time
identifies the potential linear relationship. @xref{REGRESSION}.
-@float Example, regression
+@float Example, ex-regression
@cartouche
@example
@prompt{PSPP>} get file='@value{example-dir}/repairs.sav'.