What is Science?
Decide whether the following
statements are true or false.
What is Science?
or
1. Science is concerned with
understanding how nature and the
physical world work.
2. Science can prove anything, solve
any problem, or answer any
question.
3. Any study done carefully and
based on observation is scientific.
4. Science can be done poorly.
5. Anything done scientifically can
be relied upon to be accurate and
reliable.
What is Science?
or
6. Different scientists may get
different solutions to the
same problem.
7. Knowledge of what science is,
what it can and cannot do,
and how it works, is
important for all people.
8. A hypothesis becomes a
theory which becomes a law.
9. A hypothesis is an educated
guess.
10. A general and universal
scientific method exists.
1. Science is concerned with understanding
how nature and the physical world work.
Science is a process by which we try to
understand how the natural and physical world
works and how it came to be that way.
2. Science can prove anything, solve any
problem or answer any question.
• Science actually attempts to disprove ideas
(hypotheses).
• Science is limited strictly to solving problems
about the physical and natural world.
• Explanations based on supernatural forces,
values or ethics can never be disproved and
thus do not fall under the realm of science.
3. Any study done carefully and
based on observation is scientific.
• Science must follow certain rules.
• The rules of science make the scientific
process as objective as is possible.
Objective = Not influenced by feelings,
interests and prejudices; UNBIASED
vs.
Subjective = Influenced by feelings,
interests and prejudices; BIASED
4. Science can be done poorly.
5. Anything done scientifically can be relied
upon to be accurate and reliable.
• Science can be done poorly, just like any
other human endeavor.
• Quality control mechanisms in science
increase the reliability of its product.
6. Different scientists may get different
solutions to the same problem.
• Results can be influenced by the race, gender,
nationality, religion, politics or economic
interests of the scientist.
• Sampling or measurement bias can result in
different solutions to the same problem.
7. Knowledge of what science is, what it can
and cannot do, and how it works, is important
for all people.
People need to be able to evaluate scientific information
in order to make informed decisions about:
•
•
•
•
Health care
Environmental issues
Technological advances
Public health issues
8. A hypothesis becomes a theory
which becomes a law.
• Major misconception
• There is not a natural progression
from hypothesis to theory to law
• This myth deals with the general
belief that with increased evidence
there is a developmental
sequence through which scientific
ideas pass on their way to final
acceptance
Quote of the Day:
• Theories are nets to catch what we call
“the world:” to rationalize, to explain,
and to master it. We endeavor to make
that mesh finer and finer.”
– Karl Popper (1935)
9. A hypothesis is an educated guess.
• A hypothesis is a testable statement based
upon research
• Most of the time in science class, students
are asked to propose a hypothesis during a
laboratory experience, but they are actually
giving a prediction.
• As for those hypotheses that are really
forecasts, perhaps they should simply be
called what they are, predictions.
10. A general and universal
scientific method exists.
• Scientists approach and solve problems with
imagination, creativity, prior knowledge and
perseverance.
• These are the same methods used by all
problem-solvers.
• The lesson to be learned is that science is no
different from other human endeavors when
puzzles are investigated.
So, What is Science?
• Modern science is a process by which we try
to understand how the natural world works
and how it came to be that way.
• It is NOT a process for merely collecting
"facts" about, or just describing, the natural
world, although such observations do provide
the raw material for scientific understanding.
• There is no certainty in science, only
degrees of probability (likelihood), and
potential for change.
What is Science NOT?
• Science ≠ Proof
• Science ≠ Certainty
• Science ≠ Belief
What is Science?
• Scientific understanding can always be
challenged, and even changed, with new
ways of observing, and with different
interpretations.
• The same is true of scientific facts.
• New tools, techniques, and advances in
technology have resulted in new
observations, sometimes forcing revision of
what had been taken as fact in the past.
Why is science so useful?
• The limitations are the strengths of
science.
• Scientific knowledge is the most
reliable knowledge we have about
the natural world.
• Science has enabled much of our
work in space exploration, modern
medicine, agriculture, and
technology
What is good science?
Objectivity is the key to good science.
To be objective, experiments need to be
designed and conducted in a way that
does not introduce bias into the study.
Bias = A prejudiced presentation of material
Two main types of bias:
1. Sampling bias
2. Measurement Bias
Sampling Bias
Sample = A group of units selected to be
“measured” from a larger group (the
population).
Sampling bias is introduced when the
sample used is not representative of the
population or inappropriate for the question
asked.
Factors that contribute to sampling bias
SAMPLE SIZE: Is the sample big enough to get a good
average value?
SELECTION OF SAMPLE: Does the composition of the
sample reflect the composition of the population?
Factors such as location, age, gender, ethnicity, nationality
and living environment can affect the data gathered.
How to minimize sample selection bias:
1. Use a RANDOM SAMPLE = every individual
has an equal likelihood of being chosen.
2. Limit the question asked to the specific group
sampled.
Measurement Bias
Is the method of data collection chosen in such a
way that data collected will best match reality?
Evaluate the technique:
• Measurements taken accurately
• No additions to the environment that
will influence results
• Experiment designed to isolate the
effect of multiple factors
Summary
Good science depends on a well-designed
experiment that minimizes bias by using the
appropriate:
• Sample size
• Sample selection
• Measurement techniques
***for the question being investigated
The scientific community engages in
certain quality control measures to
eliminate bias.
Results are verified by independent duplication
and publication in a peer-reviewed journal.
•Independent duplication = Two or more
scientists from different institutions investigate the
same question separately and get similar results.
•Peer-reviewed journal = A journal that publishes
articles only after they have been checked for
quality by several expert, objective scientists from
different institutions.
Identifying good science: Look for signs of bias!
• Language
• Appropriate data reported to back
conclusions
• Data source
Language
“Scientifically-proven”
* Science does not seek to prove but to disprove
* Be suspicious of this claim!
Emotional appeals
* Conclusions should be data-based
* Emotional appeals usually are not data-based
Strong language
* Scientific conclusions should only report what the
data supports.
* Words should be chosen very carefully to avoid
exaggeration or claims not supported by data.
THE DATA SHOULD CONVINCE YOU,
NOT THE WORDS USED!
Appropriate data reported to back
conclusions
Are samples and measurements
appropriate for the conclusion presented?
Are multiple factors properly accounted for
to justify the interpretation of the data?
Data Sources
1. University Research
2. Corporate Research
3. Government Research
4. Research by Special
Interest Groups
All organizations produce unbiased data. However,
it is important to understand the organization’s
motivation to be able to identify potential bias. In
some situations, the need to promote special
interests or make profits may lead to bias.
The Effects of Teen Smoking
Examining the Data Source
Investigations of Passive Smoking Harm:
Relationship between Article Conclusions & Author Affiliations
Number (%) of Reviews
Article Conclusion
Passive smoking harmful
Passive smoking not
harmful
Significance
Tobacco
Affiliated
Authors (n=31)
2 (6%)
Non-Tobacco
Affiliated Authors
(n=75)
65 (87%)
29 (94%)
10 (13%)
Χ2=60.69; P<.001
Barnes, Deborah E. 1998. Why review articles on the health effects of
passive smoking reach different conclusions. JAMA. 279(19): 1566-1570.
You are now scientists
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Learn to question
Do not prejudge
Have an open mind to topics
Realize there is more that you do not know,
than what you do know