<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Articles · Kostas Maistrelis</title><link>https://en.maistrelis.com/articles/</link><description>Personal blog of Kostas Maistrelis.</description><language>en</language><managingEditor>Kostas Maistrelis</managingEditor><webMaster>Kostas Maistrelis</webMaster><lastBuildDate>Wed, 01 Jul 2026 20:28:04 +0300</lastBuildDate><atom:link href="https://en.maistrelis.com/articles/index.xml" rel="self" type="application/rss+xml"/><item><title>Logistic Population Growth — When Space Starts to Matter</title><link>https://en.maistrelis.com/articles/logistic-growth/</link><pubDate>Wed, 01 Jul 2026 20:28:04 +0300</pubDate><author>Kostas Maistrelis</author><guid>https://en.maistrelis.com/articles/logistic-growth/</guid><description>From the exponential to the logistic equation: how the carrying capacity K of the environment turns unchecked growth into a sigmoidal curve. A standalone R Markdown lesson with qualitative analysis, phase portrait, numerical solution (deSolve) and parameter estimation.</description></item><item><title>Exponential Population Growth — From Water Lilies to the Differential Equation</title><link>https://en.maistrelis.com/articles/exponential-growth/</link><pubDate>Wed, 01 Jul 2026 18:00:00 +0300</pubDate><author>Kostas Maistrelis</author><guid>https://en.maistrelis.com/articles/exponential-growth/</guid><description>How, starting from a simple observation — a 10% daily increase in the water lilies of a lake — we arrive at the exponential growth formula by way of a differential equation. A standalone R Markdown lesson with text, R code, plots and mathematics.</description></item><item><title>Introduction to Derivatives — A Car on the Road</title><link>https://en.maistrelis.com/articles/eisagogi-paragogos/</link><pubDate>Tue, 30 Jun 2026 18:07:48 +0300</pubDate><author>Kostas Maistrelis</author><guid>https://en.maistrelis.com/articles/eisagogi-paragogos/</guid><description>A short introduction/reminder to the concept of the derivative — the «rate of change». Each lesson opens as a standalone page (R Markdown).</description></item><item><title>The Normal Distribution and its origin</title><link>https://en.maistrelis.com/articles/i-kanoniki-katanomi-kai-i-proeleysi-tis/</link><pubDate>Mon, 23 Feb 2015 21:32:16 +0200</pubDate><author>Kostas Maistrelis</author><guid>https://en.maistrelis.com/articles/i-kanoniki-katanomi-kai-i-proeleysi-tis/</guid><description>&lt;div style="float:right;margin:0 0 6px 10px;"&gt;&lt;img alt="normal_distribution" width="190" src="https://en.maistrelis.com/articles/i-kanoniki-katanomi-kai-i-proeleysi-tis/media/normal_distro1.png"&gt;&lt;/div&gt;
&lt;p&gt;Quite a few statistics and probability textbooks with an introduction to the normal distribution have passed through my hands. They almost always started with the mathematical definition and moved on to the properties and uses of the distribution. For a long time I had not found a book that explained how this formula came about — until at some point a book called Lady Luck fell into my hands which, although old, is a very good introduction to the subject of probability, and in it I found the first clear description of how the normal distribution arises.&lt;/p&gt;</description></item></channel></rss>