Statistical Analysis of Data in Science: Week 2 (9/17 – 9/21)

Post date: Sep 17, 2012 3:50:07 PM

Session 1

· Mean, Median, Mode, and Standard Deviation. We will briefly discuss how to analyze the center of a data set. We’ll practice calculating these values both by hand, and using Excel tools.

· Statistical analysis of M&Ms Lab: We will continue with our data collection, today focusing on the density of the milk chocolate M&Ms vs the Peantut (butter) M&Ms. Students will first prepare a method for determining the density, then they’ll perform their experiment, collecting raw data as they go. Students will consider the error in their measurement and will pay close attention to significant figures. The raw data will then be imported into Excel for analysis.

Session 2

· We’ll discuss the t-test and work through some examples of the t-test. We’ll also discuss the relationship between correlation and cause. Students will analyze some example data to determine if there exists causality in various cases.

· Students will analyze their t-test data and will present their finding using Internal Assessment (IA) criteria to evaluate their Data Collection and processing.

· Quick Case Study: PCBs in the Last Frontier. We’ll work through the scientific method to determine how PCBs have been transported to remote mountain lakes in Alaska.

o This interrupted case study is based on current research involving the global transport of polychlorinated biphenyls (PCBs). Students are asked to propose several hypotheses and experiments in an attempt to determine how PCBs are transferred globally. As the case unfolds, it becomes clear that the transport mechanism is more complicated than scientists first thought. The case requires minimal background knowledge and is suitable for major and non-major courses in biology, chemistry, and environmental science.

Objectives:

§ Help students review the scientific method.

§ Teach students how to better state hypotheses.

§ Encourage students to design experiments that test a hypothesis.

§ Introduce students to the scientific literature with a relatively easy-to-read article.

Session 3

· We will discuss the Chi-squared test and will use it to evaluate the color distribution in the two types of M&Ms.

· We will perform paper chromatography to analyze the dyes used in the various colors of M&Ms.

· Case Study: Eating PCBs from Lake Ontario. This case is based on an actual news release reporting on research about the effects of eating Lake Ontario fish contaminated with PCBs. It will teach students about statistical analysis and experimental design and examining how the media reports science.

o Objectives:

§ Understand that statistical analysis is simply a tool to aid in the process of conducting research.

§ Evaluate the statistical presentation of research results.

§ Examine how the media reports scientific results.