```
# NOT RUN {
set.seed(1)
x1 <- runif(200)
x2 <- sample(0:3, 200, TRUE)
distance <- (x1 + x2/3 + rnorm(200))^2
d <- datadist(x1,x2)
options(datadist="d") # No d -> no summary, plot without giving all details
f <- ols(sqrt(distance) ~ rcs(x1,4) + scored(x2), x=TRUE)
# could use d <- datadist(f); options(datadist="d") at this point,
# but predictor summaries would not be stored in the fit object for
# use with Predict, summary.rms. In that case, the original
# dataset or d would need to be accessed later, or all variable values
# would have to be specified to summary, plot
anova(f)
which.influence(f)
summary(f)
summary.lm(f) # will only work if penalty and penalty.matrix not used
# Fit a complex model and approximate it with a simple one
x1 <- runif(200)
x2 <- runif(200)
x3 <- runif(200)
x4 <- runif(200)
y <- x1 + x2 + rnorm(200)
f <- ols(y ~ rcs(x1,4) + x2 + x3 + x4)
pred <- fitted(f) # or predict(f) or f$linear.predictors
f2 <- ols(pred ~ rcs(x1,4) + x2 + x3 + x4, sigma=1)
# sigma=1 prevents numerical problems resulting from R2=1
fastbw(f2, aics=100000)
# This will find the best 1-variable model, best 2-variable model, etc.
# in predicting the predicted values from the original model
options(datadist=NULL)
# }
```

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