### ex3.1 ###### 

write.table(attitude, file = "ex1_5.csv", na = "999999", row.names = FALSE, col.names = TRUE, sep = ",")

newattitude <- read.table(file = "ex1_5.csv", na.strings = "999999", header = TRUE, sep = ",")

save(newattitude, file = "ex1_5.Rdata")

load(file = "ex1_5.Rdata")
verynewattitude <- newattitude

### ex3.2 ######

hist(attitude$rating, xlab = "Rating Scores", main = "Histogram for the rating scores", col = "pink", breaks = 10)

plot(attitude$complaints, attitude$rating)
abline(lm(rating ~ complaints, data = attitude))

median(attitude$complaints)
# comd
comd <- attitude$complaints >= 65
boxplot(attitude$rating ~ comd)

newrate <- rep(3, nrow(attitude))
newrate[attitude$rating < 60] <- 1
newrate[(attitude$rating >= 60) & (attitude$rating <= 70)] <- 2

newrate <- rep(3, nrow(attitude))
newrate[attitude$rating <= 70] <- 2
newrate[attitude$rating < 60] <- 1

newrate1 <- factor(newrate, ordered = FALSE)
newrate2 <- factor(newrate, ordered = TRUE)
obj1 <- summary(lm(attitude$raises ~ newrate1))
obj2 <- summary(lm(attitude$raises ~ newrate2))
objlist <- list(obj1, obj2)

##### Assignment 3

ex3 <- read.table("assignment3.csv", sep = ",", header = TRUE)
time2 <- rep(1, length(ex3$Time))
time2[ex3$Time > 4] <- 2
time2[ex3$Time > 8] <- 3
time2 <- factor(time2, ordered = TRUE)
ex3 <- data.frame(ex3, Time2 = time2)

table(ex3$Sex, ex3$Time2)

ex3male <- ex3[ex3$Sex == "M",]
ex3female <- ex3[ex3$Sex == "F",]

plot(ex3male$Time, ex3male$Compliance)
plot(ex3female$Time, ex3female$Compliance)

plot(c(0, 0), type = "n", xlim = c(0, 10), ylim = c(0,100), xlab = "Time", ylab="Compliance")
points(ex3male$Time, ex3male$Compliance, col = "red", pch = 2)
points(ex3female$Time, ex3female$Compliance, col = "blue", pch = 2)

boxplot(Compliance ~ Time2 + Sex, data = ex3, col = c("red", "blue", "green"))

obj <- summary(lm(Compliance ~ Personnel + Place + Method, data =ex3))

names(obj)
obj[["r.squared"]]