The scientific method and models
Reading
Scientific method: An introduction
Pease, C.M. and J.J. Bull. 2000. Science for Business, Law
and Journalism.Read Chapter 1. The need for making good choices
Chapter 2. A template for scientific inquiry
Chapter 3. How non-scientists use the scientific method
Note: This is a simple introduction to the scientific method.
This semester, we will apply
these concepts to the Grandjean et al. (1998) paper.
Models: An introduction
Pease, C.M. and J.J. Bull. 2000. Science for Business, Law and
Journalism. Read Chpt. 4 Models are
the building blocks of science and Chpt. 5
All models are false. But some are still useful.
Note: You read these chapters a couple weeks ago. Take
another look at them. They provide a broad introduction to the
concept of a model. In this class, we will find numerous examples of
models in the Grandjean et al. (1998) paper, and we will use these
models to help us understand and simplify this paper.
A key scientific paper on methylmercury
Grandjean, P. et al. 1998. Cognitive performance of children prenatally exposed to "safe" levels of methylmercury. Environmental Research, Section A 77: 165-177.
Note: Don't even think about reading this paper from
front to back. Scientists generally do not read
scientific paper from front to back, and you should not either. Read it with a view of answering the
following questions. Note well that
these question ask only that you understand this paper at the
very broadest level.
Questions for class discussion
Asking questions about science
1. Bring to class any questions you have about the science in the Grandjean et al. paper. (I really do call on students, and ask them to ask
me a question about the science.)
Scientific method (on asking the right questions)
2. Science for Business, Law and Journalism presents a 5 part template
for the scientific paper: goal, model, data, evaluation, revision.
Give an example of each part of the scientific method, drawn from
the Grandjean et al. (1998) paper.
3. What is the goal of the Grandjean et al. (1998) paper? What study
design do they employ to answer their question? What are their
major conclusions?
Models in the Grandjean et al. (1998) paper
4. Here are a very few of the many models employed by Grandjean et al. (1998),:
(i)The hypothesis, "methylmercury causes neurological defects" is a model.
(ii) The hypothesis, "PCB causes low scores on the Boston Naming Test" is also a model.
(iii) The authors use mercury concentration in the hair as a model.
(iv) The Faroe Island residents who participated in
this study is a model.
(v) The Abstract of the paper is a model.
(vi) Indeed the paper itself is a model.
(vii) A child's score on the Boston Naming test is a model.
For each model listed above, complete the following model template:
Model:
What this model substitutes for:
Type of model: (Physical, abstract, sampling)
Major assumption of this model:
Status of model: (Accepted, rejected, etc.)
Physical, abstract and sampling models
5. Provide examples that illustrate the distinction between physical, abstract and sampling models.
Why bother with models at all?
6. Why did employ the models listed above? Did they have any choice? Can a scientist simply refuse to employ models, on the grounds that any model must necessarily make untested and obviously wrong assumptions?