1. Chapter 2: Tools of Environmental Science
Section 2 – Statistics and Models

2. Statistics
Statistics – the collections and classification of data that are in the form of numbers
EX: batting averages

3. How do scientists use statistics?
Scientists use statistics to compare, summarize, characterize, and analyze data

4. How do scientists use statistics?
Statistical population = group of similar things that a scientist is interested in learning about

5. How do scientists use statistics?
Mean = the average – the number obtained by adding up the data for a given characteristic and dividing this sum by the number of individuals
What is the Mean of these numbers?
6, 11, 7
Add the numbers: = 24
Divide by how many numbers (there are 3 numbers): 24 / 3 = 8
The Mean is 8

6. How do scientists use statistics?
Distribution = the relative arrangement of the members of a statistical population

7. How do scientists use statistics?
Probability = the chance that something will happen
EX: weather

8. Models Physical model = 3-dimensional models you can touch
Graphical models = maps and graphs
Conceptual models = verbal or graphical explanation for how a system works or is organized
EX: flow chart
Mathematical model = one or more equations that represents the way a system or process works