the scientific method (or process)

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The Scientific Method (or process) Today’s agenda: 1.Let’s hear your ideas: What did you come up with, and how? 2.How do scientists do their work? Variations on the process 3.Examination of written materials and on- line journals

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The Scientific Method (or process). Today’s agenda: Let’s hear your ideas: What did you come up with, and how? How do scientists do their work? Variations on the process Examination of written materials and on-line journals . The “classic” scientific method: - PowerPoint PPT Presentation

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Page 1: The Scientific Method (or process)

The Scientific Method (or process)

Today’s agenda:1. Let’s hear your ideas: What did you come up with, and how? 2. How do scientists do their work? Variations on the process3. Examination of written materials and on-line journals

Page 2: The Scientific Method (or process)

The “classic” scientific method:1) Pose a null and one or more alternative hypotheses

What do we mean by a null hypothesis?

Why does it matter that we are trying to test or falsify a null hypothesis, rather than prove that it is true?

What are the implications of this “burden of proof”?

Page 3: The Scientific Method (or process)

The “classic” scientific method:1) Pose a null and one or more alternative hypotheses2) Conduct an experiment and record the data3) Examine the data with statistical techniques4) Reject the null hypothesis (with some risk of error),5) Or, be unable to reject the null hypothesis and so have

to accept it as correct (with some risk of ).

There will be more about these forms of error later. For now, remember that we are always estimating true distributions and relationships, and acknowledgement of the chance of making a mistake is an essential part of the scientific method.

Page 4: The Scientific Method (or process)

Experiments have two essential features:

What are they?

Page 5: The Scientific Method (or process)

Experiments have two essential features:

1) Treatment and control2) Replication

Page 6: The Scientific Method (or process)

What about other forms of analysis and inference?

Do we always need to be erecting and falsifying hypotheses?

We might want to estimate the relative effect of different processes on some complex outcome, rather than narrowly determining whether each, in isolation, has an effect or not.

We might want to estimate the relative likelihood of a series of possible outcomes, rather than just stating which is the most likely to occur.

Page 7: The Scientific Method (or process)

What about scientific approaches that do not involve experimentation?

1) Observation (animal behavior, environmental change, etc.)2) Correlation (density and growth, salinity and survival, etc.)3) Modeling (using the computer to explore scenarios, options)4) Morphology (paleontology, etc.)5) Measurements structured around some hypothesis6) Microscopical examination (new pathogens, etc.)7) Others?

Page 8: The Scientific Method (or process)

I asked my colleagues here in SAFS for input into how they do science. Here are some of their replies.

Interestingly, none used the word “experiment”.

From Ray Hilborn

As Thomas Huxley said "scepticism is the highest of duties; blind faith the one unpardonable sin".

Page 9: The Scientific Method (or process)

I asked my colleagues here in SAFS for input into how they do science. Here are some of their replies.

From Trevor Branch

I synthesize everything to try to understand the whole. So given a topic, I read every paper I can find, and gather all data sources together, and try to talk to / email every key scientist in the field. Then I write a review paper, write paper on what all the data say together, or build a model to explain all the data I collected.

Page 10: The Scientific Method (or process)

I asked my colleagues here in SAFS for input into how they do science. Here are some more replies.

From Tim Essington

I work by combining field observations with quantitative models (often using a comparative approach in lieu of experimentation), testing multiple hypotheses, to reveal patterns in nature and likely drivers therein. Lately I've been applying these approaches to study large (global) scale patterns in fisheries and to evaluate ecological responses to policy instruments.

Page 11: The Scientific Method (or process)

I asked my colleagues here in SAFS for input into how they do science. Here are some more replies.

From Bob Naiman

The essence of science as I practice it is "discovery". I try to let an ecosystem (river, riparian zone or watershed) tell me how it works ecologically to produce fish, retain its long term vitality, and exhibit resilience to change. It is the discovery, through research activities, that allow me to tell a better and better "story" as time goes by. After all, it is a good and accurate story that folks remember.

Page 12: The Scientific Method (or process)

Where do we find scientific information?

1) Peer-reviewed journals 2) Single-authored books3) Symposia or other edited, multi-authored books 4) Master’s theses and doctoral dissertations5) Agency reports6) Websites and other electronic source7) Others?

Each form of communication has strengths and weaknesses; it is important to understand their differences.

Page 13: The Scientific Method (or process)

Assignments for next class:

1) Think about your question further, and come to class with a new or more focused statement of the question.

2) Find a website or other public source of data that pertains to the question. Be creative!

3) Go to the library (there are so many to choose from!). Check out a book that is relevant to the topic and bring it to class with you.

4) Read the book’s Chapter 1, pages 5-26

Page 14: The Scientific Method (or process)

The books are lonely. Go to the library, where they live, look at them, open them, touch them, and be glad that they exist. We are lucky to have such a great library!