@alias prompt = sansserif
-@include doc/tut.texi
+@include tut.texi
@node Using PSPP
@chapter Using PSPP
Throughout this chapter reference is made to a number of sample data files.
So that you can try the examples for yourself,
-you should have received these files along with your copy of PSPP.
+you should have received these files along with your copy of PSPP.@c
@footnote{These files contain purely fictitious data. They should not be used
for research purposes.}
@note{Normally these files are installed in the directory
For example, a data set which has the variables @var{height}, @var{weight}, and
@var{name}, might have the observations:
@example
-188 89 Ahmed
-119 107 Frank
-123 67 Julie
+1881 89.2 Ahmed
+1192 107.01 Frank
+1230 67 Julie
@end example
@noindent
The following sections explain how to define a dataset.
@float Example, data-list
@cartouche
@example
-@prompt{PSPP>} data list list /forename (A12) height *.
+@prompt{PSPP>} data list list /forename (A12) height.
@prompt{PSPP>} begin data.
@prompt{data>} Ahmed 188
@prompt{data>} Bertram 167
The words @samp{data list list} are an example of the @cmd{DATA LIST}
command. @xref{DATA LIST}.
It tells PSPP to prepare for reading data.
+The word @samp{list} intentionally appears twice.
+The first occurrence is part of the @cmd{DATA LIST} call,
+whilst the second
+tells PSPP that the data is to be read as free format data with
+one record per line.
@item
The @samp{/} character is important. It marks the start of the list of
The text @samp{forename} is the name of the first variable,
and @samp{(A12)} says that the variable @var{forename} is a string
variable and that its maximum length is 12 bytes.
-The second variable's name is specified by the text @samp{height}
-and the @samp{*}
-means that this variable has the default format.
-Instead of typing @samp{*} you could also have typed @samp{(F8.2)},
-however since @samp{F8.2} is the default format (unless you changed it
-with the @cmd{SET} command (@pxref{SET})), it's quicker to simply type
-@samp{*}.
+The second variable's name is specified by the text @samp{height}.
+Since no format is given, this variable has the default format.
For more information on data formats, @pxref{Input and Output Formats}.
You can can tell the @cmd{DATA LIST} command to read the data directly from
this file instead of by manual entry, with a command like:
@example
-@prompt{PSPP>} data list file='mydata.dat' list /forename (A12) height *.
+@prompt{PSPP>} data list file='mydata.dat' list /forename (A12) height.
@end example
@noindent
Notice however, that it is still necessary to specify the names of the
1.2 RELIABILITY. Reliability Statistics
#================#==========#
-#Cronbach's Alpha#N of items#
+#Cronbach's Alpha#N of Items#
#================#==========#
# .86# 3#
#================#==========#
Researchers commonly need to test hypotheses about a set of data.
For example, she might want to test whether one set of data comes from
the same distribution as another,
-or does the mean of a dataset significantly differ from a particular
+or
+whether the mean of a dataset significantly differs from a particular
value.
This section presents just some of the possible tests that PSPP offers.
The researcher starts by making a @dfn{null hypothesis}.
Often this is a hypothesis which he suspects to be false.
For example, if he suspects that @var{A} is greater than @var{B} he will
-state the null hypothesis as @math{ @var{A} = @var{B}}.
-@footnote{This example assumes that is it already proven that @var{B} is
+state the null hypothesis as @math{ @var{A} = @var{B}}.@c
+@footnote{This example assumes that it is already proven that @var{B} is
not greater than @var{A}.}
The @dfn{p-value} is a recurring concept in hypothesis testing.