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I have found several polynomial some approximations to the Normal CDF$^{(1)}$, but my question is: are there good polynomial approximations to the Normal PDF?

Thanks

$^{(1)}$ For example, some are given in this paper.

UPDATE

To clarify my question taking advantage of the comments, I am looking for a polynomial of degree $n$, $P_n(x)$ such that, if $F(x)$ is the CDF of the standard Normal, then $F(x) \approx P_n(x)$ for $x$ in a suitable range, say $[-3,3]$.

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    Why not differentiate the "several polynomial approximations to the Normal CDF" that you have found?2012-08-15
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    @J.M. My mistake, you are absolutely right. I don't know why, but I implicitly assumed it would not have been a good approximation.2012-08-15
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    EDIT: Actually, just few of the approximations I have found are polynomial. So, I edited the original question.2012-08-15
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    @Libra Is this question now deemed answered? If so, write an answer and accept it. Maybe give an example, to make it more complete.2012-08-15
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    A quick look at the paper suggests that *polynomial approximations* is to be understood in a quite specific way (which is not, in particular, that the function is approximated by some polynomials). You might want to explain this in your post.2012-08-15
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    @did perhaps I used the term "approximation" in the wrong way. What I mean is that if $F(x)$ is the CDF of the standard normal, I am looking for a polynomial $P_n(x)$ of degree $n$ such that $F(x) \approx P_n(x)$ (I started my question focusing on the PDF, but it should be the same talking about the CDF).2012-08-15
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    And then comes the bad news: for **every** nonconstant polynomial $P$ and **every** CDF $F$, the function $(F-P)$ is unbounded. So it seems that, as I said, the assertion that $F(x)\approx P_n(x)$ is in serious need of some context.2012-08-15
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    Seen your update. On a bounded range, almost anything goes, for example Weierstrass polynomials.2012-08-15
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    You might want to look into Chebyshev economization, or minimax polynomials...2012-08-15

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