TTestw_t - script and chart function

TTestw_t() returns the aggregated t value for two independent series of values.

This function applies to two independent samples student's t-tests where the input data series is given in weighted two-column format.

If the function is used in the load script, the values are iterated over a number of records as defined by a group by clause.

If the function is used in a chart expression, the values are iterated over the chart dimensions.

Syntax:  

ttestw_t (weight, grp, value [, eq_var])

Return data type: numeric

Arguments:  

Argument Description
value The sample values to be evaluated. The sample values must be logically grouped as specified by exactly two values in group. If a field name for the sample values is not provided in the load script, the field will automatically be named Value.
weight Each value in value can be counted one or more times according to a corresponding weight value in weight.
grp The field containing the names of each of the two sample groups. If a field name for the group is not provided in the load script, the field will automatically be given the name Type.
eq_var If eq_var is specified as False (0), separate variances of the two samples will be assumed. If eq_var is specified as True (1), equal variances between the samples will be assumed.

Limitations:  

Text values, NULL values and missing values in the expression value will result in the function returning NULL.

Examples:  

TTestw_t( Weight, Group, Value )

TTestw_t( Weight, Group, Value, false )

Did this information help you?

Thanks for letting us know. Is there anything you'd like to tell us about this topic?

Can you tell us why it did not help you and how we can improve it?