Show Database Channel Statistics

Use the Database Tools > Reports > Mark Statistics menu option (STAT GX) to calculate statistics of the currently marked data in the database.

The STAT GX can also be executed from the database spreadsheet window: 

1. In the spreadsheet window select (highlight) the database channel:

• Click once to select the spreadsheet channel, click twice to select the current line data for the channel, and click three times to select the entire database channel.

2. Right-click on the selected channel to display the popup menu.

3. Select Statistics and the Stat Report dialog is displayed.

Mark Statistics dialog options

Channel	The currently selected channel. When the channel is an array channel, the included range of data windows is appended to the channel name, for example: "IP [0 to 29]".
Line(s)	The currently marked line or lines.
Fid range	The fiducial range of the selection.
Number of items	The total number of items in the selected data including dummies.
Number of valid items	The number of valid values in the selected data.
Number of dummies	The number of dummy values in the selected data.
Minimum	The minimum data value.
Maximum	The maximum data value.
Range	The difference between the highest and lowest values in the selected data.
Mean	The arithmetic mean (average) value. This is equal to the sum of all data values divided by the number of items.
Median	The median data value. This is the central value of the selected sorted data (data values are ordered from lowest to highest); for an even number of values, it is the arithmetic mean of the two middle values.
Mode	The value that occurs most frequently in the selected data.
Length-weighted mean	This field is only present for drill-hole databases containing from-to data. The values are weighted by the corresponding interval lengths equal to the difference between the "DH_To" and "DH_From" channel values. Intervals where the currently selected channel value is a dummy are not included. An asterisk "*" following the value indicates that one or more holes were skipped in a multi-hole selection because of a mis-match in the fiducial start or increment values between the channels.
Length	This field is only present for drill-hole databases containing from-to data. The Length given is the sum of the difference between the "DH_To" and "DH_From" channel values, for all intervals where the currently selected channel value is not a dummy. An asterisk "*" following the value indicates that one or more holes were skipped in a multi-hole selection because of a mis-match in the fiducial start or increment values between the channels.
Standard deviation	The standard deviation of the selected data. This is equal to the square root of the variance in the data, and it is an estimator for how far each data value lies from the mean.
Standard error	The standard error of the selected data.
Variance	The variance is calculated by taking the average of squared deviations from the mean. Like standard deviation, it is a measure of variability and indicates the degree of spread in your selected data.
Skew	The skew (degree of asymmetry) of the selected data distribution. The data distribution can exhibit right /positive skewness (the mean is greater than the median) or left /negative skewness (the mean is less than the median); a normal (symmetrical) distribution exhibits zero skewness.
Kurtosis	The kurtosis of the selected data; calculated as the proportion of data that is heavy-tailed (negative) or light-tailed (positive) in comparison with a normal distribution. A normally-distributed data exhibits a zero kurtosis.
Arithmetic sum	The sum of the selected data values.
[Save Stats]	Click this button to save the stat report to a file (see Save Stats information below).

Save Stats dialog options

New statistics file

Specify the name of the statistics file. Use the Browse button to navigate to the wanted location.

Application Notes

This GX gives a statistical report of the displayed and marked data for the selected cell or the channel for the current line.

The displayed data may not be the same as the values actually stored for the selected channel if the data has been resampled to a different fiducial increment than it was originally stored. For instance, if there is no data in a channel for a given line, then it may still appear to be populated with dummies, because, for display purposes, the values have been re-sampled to the full length of the master FID channel and filled up with dummies.

For this reason, the statistics found here may differ from statistics obtained from the line/channel report (XYZSTAT.GX).

Values from Geographic format channels are displayed using geographic format.

The "middle statistics" (minimum, maximum, range, mean, median and mode) are reported to the number of decimal places displayed in the database (and to full precision in the printed reports). The third set of statistics (standard deviation, standard error, variance, skew, and kurtosis) are reported to at least three decimal places or the number of decimals displayed in the database if that is greater.

When displaying the statistical report for the entire database only the stored data will be reported.

Scripting

This GX can be run in script mode and it produces a text file with the statistics results.

Scripting Options

Channel	Channel to compute statistics on. Script Parameter: STAT.CHAN
File	Statistics file to output. Script Parameter: STAT.FILE

Array Statistics

Array channels statistics can be viewed for:

• All elements

• Current window elements

• Defined new window elements (starting element – zero is the first element, and ending element)