# Fitting a Mixture of Gamma and Normal distribution to real data

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## Fitting a Mixture of Gamma and Normal distribution to real data

 Dear R experts, I would like to fit a mixture of gamma and normal distribution to my data in R. The data: dput(A) 0.0838, 0.081, 0.0816, 0.0838, 0.0824, 0.0871, 0.0899, 0.0938, 0.099, 0.1018, 0.0998, 0.1, 0.0955, 0.0972 Based on the data I believe (by looking at the histogram) a mixture of gamma and normal distribution is the best candidate. I used the following codes to fit the mixture distribution using fitdist function from fitdistrplus package: # Define the quantile qgm_normal <- function(p,                    w_gm=0.5,                    par_shape=2,                    par_rate=1,                    mean=0,                    sd=1) {   w_normal=1-w_gm   qgm=qgamma(p,shape=shape, rate=rate)   qnormal=qnorm(p,mean =mean,sd = sd)   return(w_gm*qgm+w_normal*qnormal) } # Define the distribution function pgm_normal <- function(q,                    w_gm=0.5,                    par_shape=2,                    par_rate=1,                    mean=0,                    sd=1) {   w_normal=1-w_gm   pgm=pgamma(q,shape=shape, rate=rate)   pnormal=pnorm(q,mean =mean,sd = sd)   return(w_gm*pgm+w_norm*pnormal) } # Define the density dgm_normal <-function(x,                   w_gm=0.5,                   par_shape=2,                   par_rate=1,                   mean=0,                   sd=1) {   w_normal=1-w_gm   dgm=dgamma(x,shape=par_shape, rate=par_rate)   dnormal=dnorm(x,mean =mean,sd = sd)   return(w_gm*dgm+w_normal*dnormal) } fit_A <- fitdist(A, "gm_normal",start=list(w_gm=0.5, par_shape=2,par_rate=1, mean=0, sd=1)) I've read the question posted here https://stackoverflow.com/questions/33942202/r-fitting-a-mixture-distribution-with-fitdistrplus   but I've got the following error: Error in fitdist(A, "gm_normal", start = list(w_gm = 0.5, par_shape = 100, : the function mle failed to estimate the parameters, with the error code 1 I could probably didn't fully understand the solution posted there. If someone could provide some help would be very grateful. Thanks in advance! -- Sent from: http://r.789695.n4.nabble.com/datatable-help-f2315188.html_______________________________________________ datatable-help mailing list [hidden email] https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help