Summarize Spreadsheet
The summarize spreadsheet dialog allows summary statistics to be generated for a
selected set of columns. The summaries can also be calculated within groups by
supplying a list of factor to cross-tabulate with. The calculated summary
statistics are displayed as variates columns within a spreadsheet along with
any factor combinations that may have been specified. The new factors and variates
are named by prefixing the original column names. For example, names are prefixed
with f_ factors and c_, m_, t_, v_, s_, d_, n_ and m_ for number of observations, means, totals,
variances, standard deviations, medians, minima and maxima respectively.
A factor that is not used in defining the groups can be included in the
summary spreadsheet using Carry button.
If there are no grouping factors specified the summary statistics for each column
are calculated using the DESCRIBE procedure.
Similarly, if the summary statistics are calculated within groups the
TABULATE directive is used.
Factors
A list of the factors in the spreadsheet which can be used to
define summary groups. Double clicking on a factor name will
place this in the Summary Groups box.
Multiple selections can be transferred by clicking the
button.
Summary Groups
Specifies a set of factors that define the groups that the summaries will
be calculated over. Factor names can be added to this list by double-clicking
on the name in the Summary Groups font, or the names
can be entered in directly. Multiple selections can be transferred from the
Summary Groups list by clicking the
button.
The groups used for the summary statistics are defined as the factorial
combination all the factors within this list. The resulting spreadsheet will
contain a row for each factor combination, whether it contains any observations
or not. If a combination is not present in the data then the summary statistics
will produce a missing value (except for counts which will be zero). The
defining factors in the summary spreadsheet are named by prefixing the
original name with the characters 'f_'.
If no factors are specified, then the summary statistics will be calculated for
using all values in each variate column.
Carry
If the summary statistics are being summarized over groups this option can be used
to maintain a factor in the spreadsheet using one of the Carry Factor Using options.
| Min | Minimum factor level in the group. |
| Median | Median factor level in the group. |
| Max | Maximum factor level in the group. |
If the factor levels are unique within each group, then the above options are ignored.
If the Warn if >1 level in summary is selected, a warning will be generated if a group contains
more than one level of the factor.
Variates
A list of available variate columns in the spreadsheet which can have
summary statistics calculated. A summary statistic for a given
column is created by selecting one or more of the columns, and then clicking the
appropriate statistic button.
Statistics
| Counts | The number of units in the group (no variate is required for this summary). | Prefix r_ |
| NOBS | The number of non missing values. | Prefix c_ |
| Mean | The mean or average value. | Prefix m_ |
| Total | The total or sum of the values. | Prefix t_ |
| Var | The variance of the values. | Prefix v_ |
| Std Dev | The standard deviation of the values. | Prefix s_ |
| Median | The median of the values. | Prefix d_ |
| Min | The minimum or smallest value. | Prefix n_ |
| Max | The maximum or largest value. | Prefix x_ |
| Percentile | The Nth percentile of the values, where N (in the range [0,100]) is supplied in the space provided.
Note that if no groups have been specified in the Summary Groups box then only
the percentiles 25%, 50% and 75% (the lower quartile, median and upper
quartile respectively) can be calculated. | Prefix q_ |
Summary Statistics
Specifies the summary statistics that are to be calculated. Different
summary statistics can be calculated simultaneously for each column and
the column order in the resulting spreadsheet will be that specified by
the order in this list.
Only keep factor combinations that are present
When selected, any combination of the grouping factors specified in the
Summary Groups list that has no observations
in it will be removed from the summary spreadsheet.
Print in Output
Prints the selected summary statistics in the output window.
Set as Active Sheet
Sets the newly created spreadsheet to be the active spreadsheet.
Merge into Original sheet
The results for the summary statistics are merged back into the spreadsheet that
is being summarized. A new column is created for each statistic where the values
are inserted using the matching factor combinations as specified in the
Factors list.
Clear
Clear the Summary Groups and Summary Statistics boxes.
OK
Calculate the requested summary statistics.
Cancel
Close the dialog without generating a summary.
See Also