exercise:088f67773d: Difference between revisions

From Stochiki
(Created page with "<div class="d-none"><math> \newcommand{\NA}{{\rm NA}} \newcommand{\mat}[1]{{\bf#1}} \newcommand{\exref}[1]{\ref{##1}} \newcommand{\secstoprocess}{\all} \newcommand{\NA}{{\rm NA}} \newcommand{\mathds}{\mathbb}</math></div> The Central Limit Theorem says the sums of independent random variables tend to look normal, no matter what crazy distribution the individual variables have. Let us test this by a computer simulation. Choose independently 25 numbers from the int...")
 
No edit summary
 
Line 1: Line 1:
<div class="d-none"><math>
The Central Limit Theorem says the sums of independent random variables tend to look normal, no matter what crazy distribution the
\newcommand{\NA}{{\rm NA}}
\newcommand{\mat}[1]{{\bf#1}}
\newcommand{\exref}[1]{\ref{##1}}
\newcommand{\secstoprocess}{\all}
\newcommand{\NA}{{\rm NA}}
\newcommand{\mathds}{\mathbb}</math></div> The Central Limit Theorem says the sums of independent
random variables tend to look normal, no matter what crazy distribution the
individual variables have.  Let us test this by a computer simulation.  Choose
individual variables have.  Let us test this by a computer simulation.  Choose
independently 25 numbers from the interval <math>[0,1]</math> with the probability
independently 25 numbers from the interval <math>[0,1]</math> with the probability
Line 13: Line 6:
same graph the density <math>\phi(x) = \mbox {normal \,\,\,}(x,\mu(S_{25}),\sigma(S_{25}))</math>.  
same graph the density <math>\phi(x) = \mbox {normal \,\,\,}(x,\mu(S_{25}),\sigma(S_{25}))</math>.  
How well does the normal density fit your bar graph in each case?
How well does the normal density fit your bar graph in each case?
<ul><li>  <math>f(x) = 1</math>.
<ul style="list-style-type:lower-alpha"><li>  <math>f(x) = 1</math>.
</li>
</li>
<li>  <math>f(x) = 2x</math>.
<li>  <math>f(x) = 2x</math>.

Latest revision as of 00:25, 15 June 2024

The Central Limit Theorem says the sums of independent random variables tend to look normal, no matter what crazy distribution the individual variables have. Let us test this by a computer simulation. Choose independently 25 numbers from the interval [math][0,1][/math] with the probability density [math]f(x)[/math] given below, and compute their sum [math]S_{25}[/math]. Repeat this experiment 1000 times, and make up a bar graph of the results. Now plot on the same graph the density [math]\phi(x) = \mbox {normal \,\,\,}(x,\mu(S_{25}),\sigma(S_{25}))[/math]. How well does the normal density fit your bar graph in each case?

  • [math]f(x) = 1[/math].
  • [math]f(x) = 2x[/math].
  • [math]f(x) = 3x^2[/math].
  • [math]f(x) = 4|x - 1/2|[/math].
  • [math]f(x) = 2 - 4|x - 1/2|[/math].