```
# NOT RUN {
x <- 1:20
y <- setNames(x + (x/4 - 2)^3 + rnorm(20, sd = 3),
paste("O", x, sep = "."))
ww <- rep(1, 20); ww[13] <- 0
summary(lmxy <- lm(y ~ x + I(x^2)+I(x^3) + I((x-10)^2), weights = ww),
cor = TRUE)
variable.names(lmxy)
variable.names(lmxy, full = TRUE) # includes the last
case.names(lmxy)
case.names(lmxy, full = TRUE) # includes the 0-weight case
# }
```

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