This text originally appeared on-line at: but disappeared from the web around 2006. My efforts to contact the author had  failed, but I was recently able to retrieve the text using the Web Archive Service. These pages were originally reconstructed from those archives. I was working to restore the figures. If you have comments on this restoral, please contact me at:  The original work was created by Richard D. Jarrard and remains his intellectual property.

Good news, as of January 16, 2008 the original work has been restored and is now available at: I have reconstructed the material here from the more recent source.

The Emotional Competency website hosts this text because of the important contribution it makes to the theory of knowledge.


an online book

Richard D. Jarrard

Dept. of Geology and Geophysics, University of Utah

Richard D. Jarrard 2001

Scientific Methods is an online book about the techniques and processes of science and the experience of being a scientist. This book is written by a scientist for scientists. My hope is that it will be browsed by scientists (including graduate students) and read by undergraduates.

Why am I publishing this book online, despite having a willing soft-cover publisher? The main reason is wider availability to readers. A typical science book has a publication run of ~2000 copies, then it goes out of print. Additional factors include educational use and ease of revision. I admit that I would have enjoyed saying that I earned ~25/hour by writing this book.

Below the Table of Contents are Adobe Acrobat PDF files, which are more printer-friendly than the web pages. The PDF files also include a Name Index and Subject Index. Feel free to print a personal copy. Note, however, that this book is copyrighted; it is unethical (see Chapter 10) and illegal to distribute multiple printouts or digital copies or to copy any of these files to other web sites.


1. Introduction
     Thumbnail History of Scientific Methods
     Myth of a Scientific Method
Scientific Methods


2. Variables
     Precision > Accuracy > Reliability
            Random and Systematic Errors
            Representative Sampling
            Replication and Confirmation
     Sampling Distribution for One Variable
     Normal Distribution
            Mean & Standard Deviation
            Normal Distribution Function
            Weighted Mean
            95% Confidence Limits on Mean
            How Many Measurements are Needed?
            Propagation of Errors
     Non-Normal Distributions
            Normality Tests
            Rejecting Anomalous Data
            Median, Range, & 95% Confidence Limits

3. Induction and Pattern Recognition
     Types of Explanation
            Plotting Hints
            Extrapolation and Interpolation
            Correlation Statistics
            Nonlinear Relationships
            Correlation Conclusions
Perspectives on Causality
     Mill's Canons: Five Inductive Methods
            Method of Agreement
            Method of Difference
            Joint Method of Agreement & Difference
            Method of Concomitant Variations
            Method of Residues
     Correlation or Causality?

4. Deduction and Logic
            Deduction vs. Induction
            Deductive Logic
     Classification Statements
            Deductive Aids: Venn Diagrams and Substitution
            Logically Equivalent Statements
            Relationships among Statements
            Categorical Syllogisms
            Hypothetical Syllogisms
     Pitfalls: Fallacious Arguments
            Fallacies Resulting from Problems in a Premise
            Fallacies Employing Extraneous Other Evidence
            Faulty Link between Premises & Conclusion
            Case-dependent Relationship between Parts & Whole

5. Experimental Techniques
     Observational versus Experimental Science
     Seizing an Opportunity
     Experimental Equipment
     Prototypes and Pilot Studies
     Troubleshooting and Search Procedures
            Problem: Find a Needle in a Haystack
            Problem: Search for the Top Quark
     Tips on Experimental Design and Execution
     Pitfalls of Experimental Design
     Control of Variables
            Problem: the Noisy Widgetometer
Computation and Information Handling


6. The Myth of Objectivity
     Perception: Case Studies
     Perception, Memory, and Schemata
     Pitfalls of Subjectivity
            Experimental Design
            Experiment Execution
            Data Interpretation
            Pitfall Examples
     Group Objectivity

7. Evidence Evaluation and Scientific Progress
     Judgment Values
     Evaluation Aids
     Confirmation and Refutation of Hypotheses
     Power of Evidence
     Hypothesis Modification
     Paradigm and Scientific Revolution
     Pitfalls of Evidence Evaluation
            Hidden Influence of Prior Theory on Evidence Evaluation
            Incremental Hypotheses and Discoveries
            'Fight or Flight' Reaction to New Ideas
            Confusing the Package and Product
            Pitfall Examples

8. Insight
     Role of Insight in Science
     Characteristics of Insight
     Conditions Favoring Insight
     Obstacles to Insight
     The Royal Way
     How Does Insight Work?
     Alternative Paths to Insight
            Unexpected Results
            Transfer from other Disciplines
            Breakthroughs by Amateurs: the Outsider Perspective
     From Puzzle Solving …
     … To Mystical Experience

9. The Scientist's World
     Scientist and Lay Person
     Science and Society
     Science and the Arts
     Science and Pseudoscience
     Applied and Basic Research
            Conflict: Applied vs. Basic Research
            Changing Goals for Applied and Basic Research
            Resolution: Bridging the Gap
     Big Science versus Little Science
     Ego and the Scientific Pecking Order

10. The Scientist
     Scientists' Characteristics
            Essential Characteristics
            Common Characteristics
     Cooperation or Competition?
     Science Ethics
     A Scientist's Life: Changing Motivations
     Process and Product


Table of Contents
1. Introduction
2. Variables
3. Induction and Pattern Recognition
4. Deduction and Logic
5. Experimental Techniques
6. The Myth of Objectivity
7. Evidence Evaluation and Scientific Progress
8. Insight
9. The Scientist's World
10. The Scientist
Name Index
Subject Index

PDF of entire book (2.2 MB)