There are assignments from Statistics by using R-studio.

## ----setup, include=FALSE------------------------------------------------ knitr::opts_chunk$set(echo = TRUE) knitr::opts_chunk$set(fig.width=8, fig.height=4) ## ------------------------------------------------------------------------ house <- read.table('Housing_Prices_GE17.txt', sep = '\t', header = TRUE) ## ------------------------------------------------------------------------ str(house) ## ------------------------------------------------------------------------ par(mfrow = c(1,2)) plot(house$Living.Area, house$Price, xlab = 'Living Area', ylab = 'Price') plot(factor(house$Bedrooms), house$Price, xlab = 'Bedrooms', ylab = 'Price') par(mfrow = c(1,2)) plot(factor(house$Bathrooms), house$Price, xlab = 'Bathrooms', ylab = 'Price') plot(factor(house$Fireplaces), house$Price, xlab = 'Fireplaces', ylab = 'Price') ## ------------------------------------------------------------------------ par(mfrow = c(1,2)) plot(house$Age, house$Price, ylab = 'Price', xlab = 'Age') house$Age.new <- house$Age + 1 plot(log10(house$Age.new), house$Price, ylab = 'Price', xlab = 'Log10(Age.new)') ## ------------------------------------------------------------------------ imod <- lm(Price ~ Living.Area + Bedrooms + Bathrooms + Fireplaces + log10(Age.new), data = house) ## ------------------------------------------------------------------------ plot(imod$fitted.values, imod$residuals, xlab = 'Fitted Values', ylab = 'Residuals') abline(0, 0) ## ------------------------------------------------------------------------ par(mfrow = c(1,2)) hist(imod$residuals, main = '', xlab = 'Residuals') qqnorm(imod$residuals) qqline(imod$residuals) ## ------------------------------------------------------------------------ summary(imod) ## ------------------------------------------------------------------------ summary(lm(Price ~ Bedrooms, data = house)) ## ------------------------------------------------------------------------ summary(lm(Price ~ log10(Age.new), data = house)) ## ------------------------------------------------------------------------ confint(imod) confint(imod, level = 0.99) ## ------------------------------------------------------------------------ data.pred <- data.frame(Living.Area = 3000, Bedrooms = 4, Bathrooms = 2.5, Fireplaces = 1, Age.new = 4+1) ## ------------------------------------------------------------------------ predict(imod, newdata = data.pred, interval = 'prediction')