# Thread: Logit regression predicted values and confidence interval

1. ## Logit regression predicted values and confidence interval

Hello I have run a logistic regression with two independent variables. I have used transformed my y(sales) and my x1(population) and x2(water).

I have my output in excel and i'm fine with the model. What I need help with is the equation for predicting values and for getting a range of predicted values based on inputting an x1 and x2 value.

Below is my output. Let say I want to predict y(sales) for the following: x1(population) = 468900 and x2(water) = 18.

What would the equation and result be? What would my confidence interval be? I know how to do this with a regular linear regression model but not with logit. Thank you!!

Coefficients Standard Error t Stat P-value Lower 95% Upper 95%
Intercept 3.338352646 1.378108305 2.422416753 0.019704791 0.559132377 6.117572915
LNWater 0.403565664 0.092098371 4.381897982 7.43601E-05 0.217831599 0.58929973
LNPop 0.671411289 0.103605576 6.480455152 7.30888E-08 0.462470732 0.880351847

2. ## Re: Logit regression predicted values and confidence interval

Hey momomath.

Do you want to predict the mean value using the population mean model or do you want to predict it using more information?

The population mean model is just logistic(mu) = B0 + B1X1 + B2X2 for your information.