On Mon, May 5, 2014 at 10:16 PM, David Winsemius <dwinsem...@comcast.net> wrote: > > On May 5, 2014, at 6:05 PM, Gabor Grothendieck wrote: > >> On Mon, May 5, 2014 at 9:43 AM, Niloofar.Javanrouh >> <javanrou...@yahoo.com> wrote: >>> >>> >>> hello, >>> i want to differentiate of L with respect to b >>> when: >>> >>> L= k*ln (k/(k+mu)) + sum(y) * ln (1-(k/mu+k)) #(negative binomial ln >>> likelihood) >>> and >>> ln(mu/(mu+k)) = a+bx #link function >>> >>> how can i do it in R? >> >> Try this. First we solve for 'mu' in terms of the other variables >> using the link equation: >> >>> library(Ryacas) >>> k <- Sym("k") >>> mu <- Sym("mu") >>> y <- Sym("y") >>> L <- Sym("L") >>> a <- Sym("a") >>> b <- Sym("b") >>> x <- Sym("x") >>> sumy <- Sym("sumy") >>> Solve(log(mu/(mu+k)) == a+b*x, "mu") >> expression(list(mu == k * exp(a + b * x)/(1 - exp(a + b * x)))) >>> >> >> Now in 'k*log(k/(k+mu)) + sumy * log(1-(k/mu+k))' substitute 'k * >> exp(a + b * x)/(1 - exp(a + b * x)))' for 'mu' using 'Subst' and take >> the derivative with respect to 'a' using 'deriv': >> >>> s <- Subst(k*log(k/(k+mu)) + sumy * log(1-(k/mu+k)), mu, >> + k * exp(a + b * x)/(1 - exp(a + b * x))) >>> deriv(s, a) >> expression(sumy * (k * ((1 - exp(a + b * x)) * (k * exp(a + b * >> x)) + k * exp(a + b * x)^2))/((1 - exp(a + b * x))^2 * (k * >> exp(a + b * x)/(1 - exp(a + b * x)))^2 * (1 - (k * (1 - exp(a + >> b * x))/(k * exp(a + b * x)) + k))) - k * ((k + k * exp(a + >> b * x)/(1 - exp(a + b * x))) * (k * ((1 - exp(a + b * x)) * >> (k * exp(a + b * x)) + k * exp(a + b * x)^2)))/((1 - exp(a + >> b * x))^2 * ((k + k * exp(a + b * x)/(1 - exp(a + b * x)))^2 * >> k))) >> > > But can we maybe get the Taylor series approximation to first or second order? >
> Taylor(d, a, 0, 2) expression(sumy * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k))) - k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/((1 - exp(b * x))^2 * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k)) + (((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k)) * (sumy * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2)))) - sumy * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)) * ((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2) + ((1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/(1 - exp(b * x))^3 + -2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x)/(1 - exp(b * x)))^2) * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k))))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k)))^2 - ((1 - exp(b * x))^2 * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k) * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2))) + k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)^2/(1 - exp(b * x))^2)) - k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))) * ((1 - exp(b * x))^2 * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))))/(1 - exp(b * x))^2 + -2 * exp(b * x) * (1 - exp(b * x)) * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k)))/((1 - exp(b * x))^2 * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k))^2) * a + a^2 * ((((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k)))^2 * ((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k)) * (sumy * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 - k * (2 * exp(b * x)^2) + k * (4 * exp(b * x)^2)))) + ((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2) + ((1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/(1 - exp(b * x))^3 + -2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x)/(1 - exp(b * x)))^2) * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k))) * (sumy * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2)))) - (sumy * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)) * (((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * ((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2))) + ((1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/(1 - exp(b * x))^3 + -2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x)/(1 - exp(b * x)))^2) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))) - (1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)) * ((1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/(1 - exp(b * x))^3 + -2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x)/(1 - exp(b * x)))^2))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2)^2 + (((1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/(1 - exp(b * x))^3 + -2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x)/(1 - exp(b * x)))^2) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2) + (((1 - exp(b * x))^3 * ((1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2))) + k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))) + -2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))) - (1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))) * (-3 * exp(b * x) * (1 - exp(b * x))^2))/(1 - exp(b * x))^6 + (-2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/(1 - exp(b * x))^3 + (-2 * exp(b * x) * (1 - exp(b * x)) - -2 * exp(b * x)^2) * (k * exp(b * x)/(1 - exp(b * x)))^2)) * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k)))) + sumy * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2))) * ((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2) + ((1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/(1 - exp(b * x))^3 + -2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x)/(1 - exp(b * x)))^2) * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k))))) - ((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k)) * (sumy * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2)))) - sumy * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)) * ((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2) + ((1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/(1 - exp(b * x))^3 + -2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x)/(1 - exp(b * x)))^2) * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k)))) * (2 * ((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2) + ((1 - exp(b * x))^2 * (k * exp(b * x) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))/(1 - exp(b * x))^3 + -2 * exp(b * x) * (1 - exp(b * x)) * (k * exp(b * x)/(1 - exp(b * x)))^2) * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k))) * ((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k)))))/((1 - exp(b * x))^2 * (k * exp(b * x)/(1 - exp(b * x)))^2 * (1 - (k * (1 - exp(b * x))/(k * exp(b * x)) + k)))^4 - (((1 - exp(b * x))^2 * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k))^2 * ((1 - exp(b * x))^2 * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k) * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 - k * (2 * exp(b * x)^2) + k * (4 * exp(b * x)^2))) + k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2)) * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)/(1 - exp(b * x))^2 + ((1 - exp(b * x))^2 * (k * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2)) * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))) - k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)^2 * (-2 * exp(b * x) * (1 - exp(b * x))))/(1 - exp(b * x))^4)) + ((1 - exp(b * x))^2 * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))))/(1 - exp(b * x))^2 + -2 * exp(b * x) * (1 - exp(b * x)) * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k)) * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2))) + k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)^2/(1 - exp(b * x))^2)) - (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))) * (((1 - exp(b * x))^2 * ((1 - exp(b * x))^2 * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2))) + 2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)^2/(1 - exp(b * x))^2)) + -2 * exp(b * x) * (1 - exp(b * x)) * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))))) - (1 - exp(b * x))^2 * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)))) * (-2 * exp(b * x) * (1 - exp(b * x))))/(1 - exp(b * x))^4 + (-2 * exp(b * x) * (1 - exp(b * x)) * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))))/(1 - exp(b * x))^2 + (-2 * exp(b * x) * (1 - exp(b * x)) - -2 * exp(b * x)^2) * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k))) + k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2))) + k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)^2/(1 - exp(b * x))^2) * ((1 - exp(b * x))^2 * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))))/(1 - exp(b * x))^2 + -2 * exp(b * x) * (1 - exp(b * x)) * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k)))) - ((1 - exp(b * x))^2 * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k) * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) - k * exp(b * x)^2 + k * (2 * exp(b * x)^2))) + k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2)^2/(1 - exp(b * x))^2)) - k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (k * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))) * ((1 - exp(b * x))^2 * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))))/(1 - exp(b * x))^2 + -2 * exp(b * x) * (1 - exp(b * x)) * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k))) * (2 * ((1 - exp(b * x))^2 * (k * ((k + k * exp(b * x)/(1 - exp(b * x))) * (2 * ((1 - exp(b * x)) * (k * exp(b * x)) + k * exp(b * x)^2))))/(1 - exp(b * x))^2 + -2 * exp(b * x) * (1 - exp(b * x)) * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k)) * ((1 - exp(b * x))^2 * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k))))/((1 - exp(b * x))^2 * ((k + k * exp(b * x)/(1 - exp(b * x)))^2 * k))^4)/2) ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.