### import the dataset [PRICES]
prices <- readxl::read_excel("state-data.xlsx", sheet="pricess")

### convert the variables into factors
prices <- readxl::read_excel("state-data.xlsx", sheet = "prices")
prices$item <- factor(prices$item)
attach(prices)

### graphical visualization
GGally::ggparcoord(prices, columns = 2:5, groupColumn = "item", scale = "uniminmax")

### Euclidean distance
dist(prices)
## scaled Euclidean distances
z.prices <- scale(prices[,2:5])
dist(z.prices)

### Manhattan distance
dist(prices, method = "manhattan")

### Minkowski metric
dist(prices, method = "minkowski", p = 3)
dist(prices, method = "maximum")

### Mahalanobis distance
biotools::D2.dist(prices[,2:5], cov(prices[,2:5]))