Biol 1441, Principles of Biology II
Principles of Evolution

Quantifying Variation

Principle

 Variation can be quantified using descriptive statistics based on the distribution pattern of the data.  Descriptive statistics is used to measure and monitor changes in populations.

Objectives

 1. Become familiar with three types of distribution patterns: Normal (Bell-shaped), and Binomial.

2.  Learn to calculate some descriptive statistics associated with a normal distribution using a calculator.

  • mean, x
  • standard deviation, sd
  • standard error of the mean, se

3. Learn to use descriptive statistics in presenting results for lab reports and assignments.

Students Need to Bring to Lab
  • graph paper
  • metric ruler
  • marking pen
  • calculator with statistical functions. Bring instruction book if need be.  
    Need stats instruction for a Texas Instrument Calculator?
    TI 89 , 9    0, Voyager 200,               TI 83         TI 82
Reading

Measuring Variation -  how descriptive statistics are used to make interpretations in biology.  

Summary of Descriptive Statistics (pdf)

Directed Investigation

Class Problem
1.  Class will use a data sets developed by the instructor.
Lab groups will work collectively to calculate descriptive statistics using their calculators.

2.  Each student will construct a graphs of the data using descriptive statistics.

3.  Instructor will demonstrate calculating descriptive statistics using the spreadsheet program, Excel.

Lab Problem
 4.  Each lab group will solve a  biology problem using descriptive stats and present  the results to the class.
Open-ended Investigation Lab Assignment (10 pts) due next week in lab  pdf