Download Tools of Environmental Science c 2

TOOLS OF ENVIRONMENTAL
SCIENCE
STATISTICS
Objectives AND MODELS
1.
Explain how scientists use statistics.
2.
Explain why the size of a statistical sample is
important.
3.
Describe three types of models commonly used
by scientists.
4.
Explain the relationship between probability and
risk.
5.
Explain the importance of conceptual and
mathematical models.
HOW DO SCIENTISTS USE STATISTICS
COLLECTIONS OF DATA THAT ARE IN THE
FORM OF NUMBERS
•Used to summarize,
characterize, analyze, and
compare data
•Used to look at statistical
populations
Statistics with Populations
•Use statistics to describe statistical
populations (a group of similar things that a
scientists is interested in learning about)
What is the Average?
•Populations are composted of individuals with
different characteristics
•Often use the average (mean) when comparing
populations
The distribution
•the relative arrangement of the members
of a statistical population
What is the probability?
•What is the chance of something happening
What is the probability of getting heads when you
toss a coin?
Why is sample size important?
STATISTICS IN EVERYDAY LIFE
Understanding the News
•The news contains statistics in everyday life.
•We have a 60% chance of rain today.
Thinking about risk
•Probability of an unwanted outcome
•You do it everyday
• Crossing a street
• Not studying for a test
•Scientists calculate the risk to large communities of people
in order to inform policy decisions in government
• Involve using data on historical events
• Projections for the future
• Scientific evidence for adverse outcomes
• Ex. The risk of getting cancer when exposed to pollution
MODELS
Representations of objects or systems
Types of models
Physical models
•DNA Model
•Skeleton
•cell
Graphical Models
•Maps
•charts
Conceptual Models
•A verbal or graphical explanation
of how a system works or organized
Mathematical Models
•One or more equations that represent the
way a cystem or process works
MAKING INFORMED DECISIONS
Objectives
1.
Describe three values that people consider when making decisions
about the environment.
2.
Describe the four steps in a simple environmental decision-making
model.
3.
Compare the short-term and long-term consequences of two decisions
regarding a hypothetical environmental issue.
AN ENVIRONMENTAL DECISION-MAKING
MODEL
Conceptual model that
provides
a systematic process
for making decisions
How to use the Decision Making
Model
•Gather Information
•Consider values
•Explore consequences
•Make your decision!