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Re: Draw approximated normal distribution based on mean, median, percentiles?

• To: mathgroup at smc.vnet.net
• Subject: [mg70116] Re: Draw approximated normal distribution based on mean, median, percentiles?
• From: "Ray Koopman" <koopman at sfu.ca>
• Date: Wed, 4 Oct 2006 05:59:18 -0400 (EDT)
• References: <eftdpe$6d6$1@smc.vnet.net>

rflaaten at start.no wrote:
> Hello all,
>
> I searched the forum for any info on this, so here goes.
>
> I need to reference some statistical data from a study. The information
> given there for an age distribution is: mean, standard deviation,
> median plus the 25th and 75th percentiles. Now, I have tried in vain to
> get Excel or SPSS to draw this for me. Is there any way of inputting
> percentiles and median into Mathematica? The normal distribution
> function only takes mean and sd as far as I know.
>
>
> Any help would be much appreciated.
> Richard

For a normal distribution,  mean = median = x50
and  sd = .7413*(x75 - x25).