TTest1w_lower() returns the aggregated value for the lower end of the confidence interval for a series of values.
This function applies to one-sample 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:
TTest1w_lower (weight, value [, sig ])
Return data type: numeric
Arguments:
- value: The samples to be evaluated. 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.
- sig: The two-tailed level of significance can be specified in sig. If omitted, sig is set to 0.025, resulting in a 95% confidence interval.
Limitations:
Text values, NULL values and missing values in the expression value will result in the function returning NULL.
Examples:
TTest1w_lower( Weight, Value )
TTest1w_lower( Weight, Value, 0.005 )
