2010-03-03-beetle-population-dynamics-forecast.html

--- 
type: post
status: publish
published: true
title: Beetle population dynamics forecast
meta: 
  _edit_last: "2"
tags: 
- PSTAT 262
layout: post
---
<span style="font-size:85%;">This [unedited] guest post is by a student in my PSTAT262MC class (<a title="Student blogging background" href="http://jaradniemi.com/blog/2010/03/03/student-forecasts/" target="_self">background post</a>).
Please praise/critique/comment on its quality and importance to you.</span><hr>

A laboratory strain of <a href="http://en.wikipedia.org/wiki/Callosobruchus_maculatus"><em>Callosbruchus maculatus</em></a>, a beetle, was used to study population dynamics. Initially 50 beetles were placed in a main container with 1 petri dish containing 5g of beans. Every 3 days 5g of fresh beans were added to this container on a new petri dish while petri dishes with beans that had been added 18 days earlier were transferred to a separate `emergence' container. Adults found in the emergence container were transfered to the main container. Three replicates of this experiment counting total adult beetles every 3 days for a total of 408 days are shown in the figure below. My forecast (95% interval) for the number of beetles on day 414 and day 438 are 100 (90, 110) and 300 (275, 325), respectively.

<img class="aligncenter" title="Google Mars" src="http://jaradniemi.com/blog/includes/class/pstat262mc/beetle.jpg" alt="" width="580" />