Statistical Analysis

 

This section offers a brief overview of how DADiSP can be used as a visual, statistical analysis tool on both single series and matrices of data.

Single Series Stats

The following is a partial list of standard statistical and math functions that can be applied to a single variable data series. You can access most of these functions through the Math and Statistics option on the Analysis pull-down menu.

 

Function

Description

AMPDIST

Calculates amplitude distribution.

AREA

Calculates the area under a curve.

DERIV

Takes the derivative of a series.

GRADE

Sorts a series in ascending or descending order and yields an output series containing the indices (i.e., observation numbers) of the sorted input series.

INTEG

Integrates a series.

LENGTH

Displays the length of a series.

LINREG

Determines linear regression.

LINREG2

Calculates linear regression of two.

LOOKUP

Picks selected points by index.

MEAN

Calculates the mean.

MEDIAN

Calculates the median.

PARTSUM

Calculates the partial sum.

REORDER

Rearranges a series based upon specified indices.

SORT

Re-arranges the y values of a series in ascending or descending numerical order.

STATS

Displays MEAN and STDEV.

STDEV

Provides the standard deviation.

 

 

REORDER is similar to SORT, however, it works much faster on larger series. For example,

 

reorder(w1, grade(w1))

 

produces the same result as SORT(W1). Now try this:

 

reorder(sort(w1),grade(grade(w1),1))