Adjust the mixture parameters (weight, means and variances):
Legend:
"Mixture" = w1 N(m1, v1) + w2 N(m2, v2), with w2 = 1-w1.
"Component 1" = w1 N(m1, v1), "Component 2" = w2 N(m2, v2).
"Total normal" = normal distribution with mean m0 and variance v0.
v.within = within-group variance, v.between = between-group variance.
m0 = total mean, v0 = total variance = v.within + v.between.
t^2 = (m1-m2)^2 / (v1/w1+v2/w2) = squared t-score.
t_pool^2 = v.between/v.within = squared pooled variance t-score.