Hello kind souls,
I am using S-plus 6.2. I am new to the "bootstrap" function in S-plus. I have
looked at S-plus Help and this list-serve for previous questions similar to
mine and I am still stuck.
I performed a logistic regression using the GUI. In the "Predict" tab, I
selected "Prediction Type" "response." The data frame was: P100.A300. The
best model was "model3":
P ~ X1 + X2 + X3 + X4 + as.factor(X5)
I got a column of predicted response values (probabilities ranging from 0 to 1).
Now I want to resample (via bootstrap) the predicted response and use it to
test/validate my model.
I tried using the "Statistics -> "Resample" -> "Bootstrap" option. My question
is, what do I type into the "Expression" box to do this?
S-plus Help says, "For example, to bootstrap or jackknife the regression
coefficients for regressing Mileage on Weight in the fuel.frame data, use the
expression coef(lm(Mileage~Weight, fuel.frame)) and specify fuel.frame as the
Data Set."
So, trying to follow this logic, I typed in the ?Expression? box:
response(model3(P ~ X1 + X2 + X3 + X4 + as.factor(X5)), P100.A300))
I get the error:
"11: eval(action, sys.parent())
10: doErrorAction("Problem in eval(statistic, c(list(P100.A300..: Couldn't find
a function definition for \"model3\"",
9: response(model3(P ~ X1 + X2 + X3 +
8: eval(statistic, c(list(P100.A300 = data), data))
7: eval(statistic, c(list(P100.A300 = data), data))
6: fit.func(1:n, data, statistic, args.stat)
5: bootstrap(data = P100.A300, statistic = response(model3(
4: eval(fun.call)
3: menuBootstrap(data = P100.A300, statistic = response(
2: eval(expression(menuBootstrap(data = P100.A300, statistic =
1: Message: Problem in eval(statistic, c(list(P100.A300..: Couldn't find a
function definition for "model3""
What should I type in the ?Expression? box to resample (via bootstrap) the
column of predicted response values (probabilities ranging from 0 to 1) from my
model so I can test/validate it?
Thank you so much for your help.
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