The Scientific Method

An Introduction to the Inquiry Process

By Keith CarlsonDept. of AnthropologyUniversity of Arizona

How do scientists know what they know?

Why is the sky blue?

Why does it rain?

How did people live in the past?How old is the Earth?

Answer….

THE SCIENTIFIC METHOD!!!

A step-by-step process scientists use to

answer questions and solve problems.

The steps of the Scientific Method are:

THE SCIENTIFIC METHOD1) Research Question:The problem or issue you want to learn more about.

2) Hypothesis:Testable Prediction that follows from your research question that can be

tested and evaluated.

3) Methods:What will be your procedures for testing your hypothesis?

4) Data Collection:Record observations regarding data related to the problem you are

interested in.

5) Inferences/InterpretationWhat can you say about your hypothesis based on your observations? Is

your hypothesis supported by your observations?

6) Sharing your conclusionsScientists write reports and give presentations to inform others about

their research!

Applying the Scientific Method:Archaeology

What’s Archaeology and Who’s anArchaeologist?

• Archaeology:• The study of human

activity and the past through material remains

• Archaeologist: • A scientist who studies

humans, past and present, through their material remains

• Uses the Scientific Method!!!

• Not all archaeologists study the past!

• Some investigate material remains from our own society!!!

Bill Rathjehttp://www.psihoyos.com/pages/Stock/Portraits/rathje-william/pages/rathje-william0001.html

The Garbology Project

From: Rubbish: The Archaeology of Garbage, by William Rathje and Cullen Murphy. The University of Arizona Press, Tucson, 2001

The Garbage Project• Began at the University of Arizona in 1973• As part of their research method, project personnel have

studied over 250,000 lbs of garbage from American households and Landfills since 1973.

• Research Question:• What can we learn about our own

society from the garbage we throw away?

Hypotheses

First, what hypotheses do you have about what the garbologists would find in the typical American garbage and in Landfills?

The Garbage Project developed several hypotheses and questions based on questionnaires and other general knowledge….

Hypotheses and Specific Questions the Garbology

Project Generated:

1) Landfills are filling up with fast food packaging and lots of plastic waste – as based on surveys of what many Americans think is in our waste.

2) Paper and food products biodegrade over time.

3) What is the relationship between what people say they do and eat, and what is actually found in their garbage?

Methods and Data CollectionHow would you test the hypothesis?

Systematically excavate, or dig in landfill….

metamedia.stanford.edu

• Randomly collect household garbage….

Methods and Data Collection

… sort contents layer by layer and bag by bag …

http://metamedia.stanford.edu/projects/GarbologyOnline

Methods and Data Collection

… and record observations about what You find!!!

Rathje and Murphy (2001:73)

2) Plastic bottles, soda cans, and fast foodpackaging less than 1%!!!3) Items such as lettuce and old fruit lasted over 15 years!

Project Observations: 1) Landfills contain almost 40%

newspapers between 15 and 40 years old!!!

Inferences - What do the observations mean?

Do the observations support the hypotheses?

NO!!!

Landfills are not filling up with plastics, but with paper and construction products. Items that we

would expect to decompose do not always.

Recycling of paper products, in addition to plastics,is not a major activity in modern society in comparison to the total amount of garbage!

Conclusions

1) Recycling, especially of paper, needs to be a PRIORITY!2) People need to find ways to compost! 3) What people think is in their garbage is not necessarily

what is really there!!! and……1) What people say they eat and do is not always

necessarily the case!

Important references• From: Rubbish: The Archaeology of Garbage, by William Rathje and Cullen Murphy.

The University of Arizona Press, Tucson, 2001

• http://metamedia.stanford.edu/ projects/GarbologyOnline