which-formula-is-used-when-variances-are-unequal

Question

Which formula is used when variances are unequal?

Accepted Answer

t_{calculated }= (x_{1} - x_{2}) / √((s_{1}^{2}/n_{1}) + (s_{2}^{2}/n_{2}))

Answer

t_{calculated }= (x_{1} - x_{2}) / (s_{1} + s_{2})

Answer

t_{calculated }= (x_{1} - x_{2}) / s_{1}

Answer

t_{calculated }= (x_{1} - x_{2}) / s_{pooled}