7.11 Predictive Models

Randomly chosen sample locations for training data; red: water, yellow: land
Randomly chosen sample locations for training data; red: water, yellow: land
image code 
plot(r[,,,1], reset = FALSE)
col <- rep("yellow", 20)
col[c(8, 14, 15, 18, 19)] = "red"
st_as_sf(e) |> st_coordinates() |> text(labels = 1:20, col = col)
rs <- split(r)
trn <- st_extract(rs, pts)
trn$cls <- rep("land", 20)
trn$cls[c(8, 14, 15, 18, 19)] <- "water"
model <- MASS::lda(cls ~ ., st_drop_geometry(trn)) #linear discriminant analysis
pr <- predict(rs, model)
plot(pr[1], key.pos = 4, key.width = lcm(3.5), key.length = lcm(2))