# T-test functions T-test functions are used for statistical examination of two population means. A two-sample t-test examines whether two samples are different and is commonly used when two normal distributions have unknown variances and when an experiment uses a small sample size. In the following sections, the t-test statistical test functions are grouped according to the sample student test that applies to each type of function. Use the drop-down on each function to see a brief description and the syntax of each function. Click the function name in the syntax description for further details. [Creating a typical t-test report](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest_t_example.htm) ## Two independent samples t-tests The following functions apply to two independent samples student's t-tests: [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest\_conf TTest\_conf returns the aggregated t-test confidence interval value for two independent samples. [**ttest_conf**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest_conf.htm) ( grp, value [, sig[, eq\_var]]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest\_df TTest\_df() returns the aggregated student's t-test value (degrees of freedom) for two independent series of values. [**ttest_df**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest_df.htm) (grp, value [, eq\_var) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest\_dif TTest\_dif() is a numeric function that returns the aggregated student's t-test mean difference for two independent series of values. [**ttest_dif**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest_dif.htm) (grp, value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest\_lower TTest\_lower() returns the aggregated value for the lower end of the confidence interval for two independent series of values. [**ttest_lower**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest_lower.htm) (grp, value [, sig[, eq\_var]]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest\_sig TTest\_sig() returns the aggregated student's t-test 2-tailed level of significance for two independent series of values. [**ttest_sig**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest_sig.htm) (grp, value [, eq\_var]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest\_sterr TTest\_sterr() returns the aggregated student's t-test standard error of the mean difference for two independent series of values. [**ttest_sterr**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest_sterr.htm) (grp, value [, eq\_var]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest\_t TTest\_t() returns the aggregated t value for two independent series of values. [**ttest_t**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest_t.htm) (grp, value [, eq\_var]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest\_upper TTest\_upper() returns the aggregated value for the upper end of the confidence interval for two independent series of values. [**ttest_upper**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest_upper.htm) (grp, value [, sig [, eq\_var]]) ## Two independent weighted samples t-tests The following functions to two independent samples student's t-tests where the input data series is given in weighted two-column format: [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttestw\_conf TTestw\_conf() returns the aggregated t value for two independent series of values. [**ttestw_conf**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttestw_conf.htm) (weight, grp, value [, sig[, eq\_var]]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttestw\_df TTestw\_df() returns the aggregated student's t-test df value (degrees of freedom) for two independent series of values. [**ttestw_df**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttestw_df.htm) (weight, grp, value [, eq\_var]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttestw\_dif TTestw\_dif() returns the aggregated student's t-test mean difference for two independent series of values. [**ttestw_dif**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttestw_dif.htm) ( weight, grp, value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttestw\_lower TTestw\_lower() returns the aggregated value for the lower end of the confidence interval for two independent series of values. [**ttestw_lower**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttestw_lower.htm) (weight, grp, value [, sig[, eq\_var]]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttestw\_sig TTestw\_sig() returns the aggregated student's t-test 2-tailed level of significance for two independent series of values. [**ttestw_sig**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttestw_sig.htm) ( weight, grp, value [, eq\_var]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttestw\_sterr TTestw\_sterr() returns the aggregated student's t-test standard error of the mean difference for two independent series of values. [**ttestw_sterr**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttestw_sterr.htm) (weight, grp, value [, eq\_var]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttestw\_t TTestw\_t() returns the aggregated t value for two independent series of values. [**ttestw_t**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttestw_t.htm) (weight, grp, value [, eq\_var]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttestw\_upper TTestw\_upper() returns the aggregated value for the upper end of the confidence interval for two independent series of values. [**ttestw_upper**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttestw_upper.htm) (weight, grp, value [, sig [, eq\_var]]) ## One sample t-tests The following functions apply to one-sample student's t-tests: [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1\_conf TTest1\_conf() returns the aggregated confidence interval value for a series of values. [**ttest1_conf**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1_conf.htm) (value [, sig]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1\_df TTest1\_df() returns the aggregated student's t-test df value (degrees of freedom) for a series of values. [**ttest1_df**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1_df.htm) (value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1\_dif TTest1\_dif() returns the aggregated student's t-test mean difference for a series of values. [**ttest1_dif**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1_dif.htm) (value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1\_lower TTest1\_lower() returns the aggregated value for the lower end of the confidence interval for a series of values. [**ttest1_lower**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1_lower.htm) (value [, sig]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1\_sig TTest1\_sig() returns the aggregated student's t-test 2-tailed level of significance for a series of values. [**ttest1_sig**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1_sig.htm) (value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1\_sterr TTest1\_sterr() returns the aggregated student's t-test standard error of the mean difference for a series of values. [**ttest1_sterr**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1_sterr.htm) (value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1\_t TTest1\_t() returns the aggregated t value for a series of values. [**ttest1_t**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1_t.htm) (value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1\_upper TTest1\_upper() returns the aggregated value for the upper end of the confidence interval for a series of values. [**ttest1_upper**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1_upper.htm) (value [, sig]) ## One weighted sample t-tests The following functions apply to one-sample student's t-tests where the input data series is given in weighted two-column format: [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1w\_conf TTest1w\_conf() is a numeric function that returns the aggregated confidence interval value for a series of values. [**ttest1w_conf**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1w_conf.htm) (weight, value [, sig]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1w\_df TTest1w\_df() returns the aggregated student's t-test df value (degrees of freedom) for a series of values. [**ttest1w_df**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1w_df.htm) (weight, value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1w\_dif TTest1w\_dif() returns the aggregated student's t-test mean difference for a series of values. [**ttest1w_dif**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1w_dif.htm) (weight, value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1w\_lower TTest1w\_lower() returns the aggregated value for the lower end of the confidence interval for a series of values. [**ttest1w_lower**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1w_lower.htm) (weight, value [, sig]) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1w\_sig TTest1w\_sig() returns the aggregated student's t-test 2-tailed level of significance for a series of values. [**ttest1w_sig**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1w_sig.htm) (weight, value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1w\_sterr TTest1w\_sterr() returns the aggregated student's t-test standard error of the mean difference for a series of values. [**ttest1w_sterr**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1w_sterr.htm) (weight, value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1w\_t TTest1w\_t() returns the aggregated t value for a series of values. [**ttest1w_t**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1w_t.htm) ( weight, value) [](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/t_tests.htm) #### ttest1w\_upper TTest1w\_upper() returns the aggregated value for the upper end of the confidence interval for a series of values. [**ttest1w_upper**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/ChartFunctions/StatisticalTestFunctions/ttest/ttest1w_upper.htm) (weight, value [, sig])