search for: phat1

Quick question: Which function do you use to calculate partial derivatives from a model equation? I've looked at deriv(), but think it gives derivatives, not partial derivatives. Of course my equation isn't this simple, but as an example, I'm looking for something that let's you control whether it's a partial or not, such as: somefunction(y~a+bx, with respect to x,

...re is my attempt: ### Variables for an observation x01 <- 0.2 x02 <- 0.1 ### Parameters for an observation b00.1 <- 0.5 b00.2 <- 0.3 b00.3 <- 0 b01.1 <- 0.4 b01.2 <- 0.5 b01.3 <- 0 b02.1 <- 0.3 b02.2 <- -0.1 b02.3 <- 0 ### Predicted Probabilities for an observation phat1 <- 0.6 phat2 <- 0.3 phat3 <- 0.1 ### Correct way to calculate a partial derivative partial.b01.1 <- phat1 * (b01.1 - (b01.1*phat1+b01.2*phat2+b01.3*phat3)) partial.b01.2 <- phat2 * (b01.2 - (b01.1*phat1+b01.2*phat2+b01.3*phat3)) partial.b01.3 <- phat3 * (b01.3 - (b01.1*phat1+b01....