H, I have a question where I am not sure if what I calculated is correct.

So there are two therapies, A and B with 48/60 and 25/40 being healed respectively.

I now should calculate the confidence Intervalle for the difference of „proportions“ ( not sure what the English term is, i tried to look it up, but cant find anything useful) I am using the formula

$$(p_1-p_2 )+-Q_(1-\alpha/2)(N(0,1))* \sqrt{p_1(1-p_1)/n_1 + p_2(1-p_2)/n_2}$$

I am still getting used to math Jax....

So that would give me (-1/200, 71/200) And that negative sign just makes no sense imho. How can a proportion be negative.... but i cant find where i made the mistake....

I would be so grateful for your help :)

H, I have a question where I am not sure if what I calculated is correct.

So there are two therapies, A and B with 48/60 and 25/40 being healed respectively. I shall calculate the 95% CI

I now should calculate the confidence Intervalle for the difference of „proportions“ ( not sure what the English term is, i tried to look it up, but cant find anything useful) I am using the formula

$$(p_1-p_2 )+-Q_(1-\alpha/2)(N(0,1))* \sqrt{p_1(1-p_1)/n_1 + p_2(1-p_2)/n_2}$$

I am still getting used to math Jax....

So that would give me (-1/200, 71/200) And that negative sign just makes no sense imho. How can a proportion be negative.... but i cant find where i made the mistake....

I would be so grateful for your help :)