How can I use a trained and tested algorithm (eg. machine learning classifier) after being saved, on a new observation/dataset, whose I do not know the class (eg. ill vs healthy) based on predictors used for model training? I use caret but can't find any lines of code for this. many thanks
After training and testing any machine learning model you can save the model as .rds
file and call it as
#Save the fitted model as .rds file
saveRDS(model_fit, "model.rds")
my_model <- readRDS("model.rds")
Creating a new observation from the same dataset or you can use a new dataset also
new_obs <- iris[100,] #I am using default iris dataset, 100 no sample
Prediction on the new observation
predicted_new <- predict(my_model, new_obs)
confusionMatrix(reference = new_obs$Species, data = predicted_new)
table(new_obs$Species, predicted_new)