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DIR Return to: Questions for R / RStudio (Spring 2023)
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#Post#: 60--------------------------------------------------
Question for practice exam problem1
By: Cat Date: February 26, 2023, 11:33 pm
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I'm quite confusing since I get an inverse function
inv.fun <- function(x){
result <- -log(-x)
return <- 4*sqrt(result)
}
like this. However, the domain of this function is all negative
complex numbers which seems to be not correct.
I'm not sure if someone else get a different function or I
should continue.
Thank you :)
#Post#: 61--------------------------------------------------
Re: Question for practice exam problem1
By: Cat Date: February 26, 2023, 11:36 pm
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Just make a correction, the function should be
inv.fun <- function(x){
result <- -log(1-x)
return <- 4*sqrt(result)
}
but the domain is still confusing ???
#Post#: 62--------------------------------------------------
Re: Question for practice exam problem1
By: Taeho Kim Date: February 27, 2023, 6:19 am
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Hi Cat,
The function looks okay, but we need to use the return()
properly.
Since this is an inverse function the domain is between 0 and 1
and the range would be corresponding positive values.
#Post#: 63--------------------------------------------------
Re: Question for practice exam problem1
By: Cat Date: February 27, 2023, 5:46 pm
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I'm sorry Darth Knight, but I still cannot find the correct
inverse function here.
I currently get the cdf to be F(x) = -exp[(-x^2)/16] + 1
And I always end up with the inverse function
f(x) = sqrt(-16*ln(1-x)) which does not make sense.
I guesss there exists some error on my integral but I do not
know where it is... :-[ :-[ :-[
#Post#: 64--------------------------------------------------
Re: Question for practice exam problem1
By: Taeho Kim Date: February 28, 2023, 4:28 pm
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Hi Cat,
I think the issue was in the inversion.
Please see the solution of the practice exam.
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