# Independent Samples - Survey Reporter Column Means Test

By default, when this test is selected Q computes standard errors using *Taylor series linearization*. To replicate the results of IBM SPSS Data Collection Model programs (e.g., Survey Reporter), you need to also change the **Weights and significance** to **Kish approximation** in Statistical Assumptions.

Where *Taylor series linearization* is performed, and and are the two means, the test statistic is:

Otherwise, the test statistic is:

where:

- and refer to the two variables,
- is the sample size,
- is the effective sample size,
- is the weighted sample size,
- is the weight for the th observation in the th group,
- if
**Bessel's correction**is selected and 0 otherwise, - ,
- is the Standard Error of the mean,
- the p is returned as NaN if the denominator is less than 0.00001.