Many thanks. May be I need to check my eyes before anything!!!
On Sat, Jul 13, 2024 at 6:46 PM Rui Barradas <ruipbarra...@sapo.pt> wrote: > > Às 12:13 de 13/07/2024, Christofer Bogaso escreveu: > > Hi, > > > > I ran below code > > > > Dat = > > read.csv('https://raw.githubusercontent.com/sam16tyagi/Machine-Learning-techniques-in-python/master/logistic%20regression%20dataset-Social_Network_Ads.csv') > > head(Dat) > > Model = glm(Purchased ~ Gender, data = Dat, family = binomial()) > > head(predict(Model, type="response")) > > My_Predict = 1/(1+exp(-1 * (as.vector(coef(Model))[1] * > > as.vector(coef(Model))[2] * ifelse(Dat['Gender'] == "Male", 1, 0)))) > > head(My_Predict) > > > > However, My_Predict and predict(Model, type="response")) are differing > > when I tried to manually calculate prediction. > > > > Could you please help to identify what was the mistake I made? > > > > ______________________________________________ > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > > 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. > Hello, > > Sometimes when there is an error, the best way to correct it is to > rewrite the offending part of the code. > In your case, after as.vector(coef(Model))[1] you should have a plus sign. > > > > Dat = > read.csv('https://raw.githubusercontent.com/sam16tyagi/Machine-Learning-techniques-in-python/master/logistic%20regression%20dataset-Social_Network_Ads.csv') > head(Dat) > Model = glm(Purchased ~ Gender, data = Dat, family = binomial()) > > # use matrix algebra > x <- cbind(1, (Dat$Gender == "Male")) %*% coef(Model) > pred1 <- exp(x)/(1 + exp(x)) > > # use the fitted line equation > y <- coef(Model)[1L] + coef(Model)[2L] * (Dat$Gender == "Male") > pred2 <- exp(y)/(1 + exp(y)) > > head(predict(Model, type="response")) > head(pred1) |> c() > head(pred2) > > > Hope this helps, > > Rui Barradas > > > -- > Este e-mail foi analisado pelo software antivírus AVG para verificar a > presença de vírus. > www.avg.com ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.