the mean and std value of a standard normal distribution

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Hello,
I used matlab example https://www.mathworks.com/help/stats/normal-distribution.html
Compute the pdf of a standard normal distribution, with parameters µ equal to 0 and σ equal to 1. The mean value of norm should be 0, and the std value of norm should be 1.
Why the mean value of norm is 0.1636, and the std value is 0.1408?
Thanks in advance!
Yue
x = [-3:.1:3];
norm = normpdf(x,0,1);
>> norm_mean=mean(norm)
norm_mean =
0.1636
>> norm_std=std(norm)
norm_std =
0.1408
  2 Commenti
Adam
Adam il 28 Ago 2018
You are taking the mean and std of the values on the y axis of the pdf, not the x axis, which is a fairly meaningless statistic.
yue li
yue li il 28 Ago 2018
Modificato: yue li il 28 Ago 2018
Hello, Adam,
Thank you so much for your great help!
Yue

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Image Analyst
Image Analyst il 28 Ago 2018
norm() is a built-in function so don't use that for your variable name.
Try using randn() and then using mean() and std() on that.

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