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August 25, 2016 00:37
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Multilabel classification using R and the neuralnet package
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################################################################################ | |
# Loading data | |
rm( list=ls() ) | |
# load libs | |
require(neuralnet) | |
require(nnet) | |
# Load data and set names | |
wines <- read.csv("wines.csv") | |
names(wines) <- c("label", | |
"Alcohol", | |
"Malic_acid", | |
"Ash", | |
"Alcalinity_of_ash", | |
"Magnesium", | |
"Total_phenols", | |
"Flavanoids", | |
"Nonflavanoid_phenols", | |
"Proanthocyanins", | |
"Color_intensity", | |
"Hue", | |
"OD280_OD315_of_diluted_wines", | |
"Proline") | |
################################################################################ | |
# Preprocessing | |
# Encode as a one hot vector multilabel data | |
train <- cbind(wines[, 2:14], class.ind(as.factor(wines$label))) | |
# Set labels name | |
names(train) <- c(names(wines)[2:14],"l1","l2","l3") | |
# Scale data | |
scl <- function(x){ (x - min(x))/(max(x) - min(x)) } | |
train[, 1:13] <- data.frame(lapply(train[, 1:13], scl)) | |
head(train) | |
################################################################################ | |
# Fitting | |
# Set up formula | |
n <- names(train) | |
f <- as.formula(paste("l1 + l2 + l3 ~", paste(n[!n %in% c("l1","l2","l3")], collapse = " + "))) | |
f | |
nn <- neuralnet(f, | |
data = train, | |
hidden = c(13,10,3), | |
act.fct = "logistic", | |
linear.output = FALSE, | |
lifesign = "minimal") | |
summary(nn) | |
# Compute predictions | |
pr.nn <- compute(nn, train[, 1:13]) | |
# Extract results | |
pr.nn_ <- pr.nn$net.result | |
head(pr.nn_) | |
# Accuracy (training set) | |
original_values <- max.col(train[, 14:16]) | |
pr.nn_2 <- max.col(pr.nn_) | |
mean(pr.nn_2 == original_values) | |
################################################################################ | |
# Crossvalidate | |
set.seed(10) | |
k <- 10 | |
outs <- NULL | |
proportion <- 0.995 | |
library(plyr) | |
pbar <- create_progress_bar('text') | |
pbar$init(k) | |
for(i in 1:k) | |
{ | |
index <- sample(1:nrow(train), round(proportion*nrow(train))) | |
train_cv <- train[index, ] | |
test_cv <- train[-index, ] | |
nn_cv <- neuralnet(f, | |
data = train_cv, | |
hidden = c(13, 10, 3), | |
act.fct = "logistic", | |
linear.output = FALSE) | |
# Compute predictions | |
pr.nn <- compute(nn_cv, test_cv[, 1:13]) | |
# Extract results | |
pr.nn_ <- pr.nn$net.result | |
# Accuracy (test set) | |
original_values <- max.col(test_cv[, 14:16]) | |
pr.nn_2 <- max.col(pr.nn_) | |
outs[i] <- mean(pr.nn_2 == original_values) | |
pbar$step() | |
} | |
# Average accuracy | |
mean(outs) |
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Do you think it needs be rounded in Accuracy part?