| Science Is a Way of Knowing
Science
1. An organized way of gathering
& analyzing evidence about the natural world
A process
of investigation, carried out under certain rules, through observation
and the
testing of hypotheses
2. A body of factual knowledge
about the natural world gathered through this process
3. A collection of theories
that explains this knowledge,
with predictive
ability about nature,
the evidence
for which is an array of facts
The Elements of Scientific Information:
Fact
A phenomenon about which competent
observers who have made a series of observations agree—verified data
Law or Principle
A general statement about the relationship
of facts that does not explain, but has been repeatedly and consistently
tested without being disproved
Theory
A general set of laws or principles,
supported without contradiction by evidence, that explains and reliably
predicts some aspect of nature.
The Realm of Scientific Inquiry
-
Science is concerned with natural explanations
for natural phenomena.
Supernatural explanations & phenomena
are outside the realm of science and cannot be examined through the scientific
process.
The Goals of Science
-
One goal of science is to provide natural
explanations for events in the natural world.
-
Science also aims to use those explanations
to understand patterns in nature and to make useful predictions about natural
events.
What is science?
REVIEW & DO
NOW
Answer the following questions: |
| What is science?
Distinguis between a fact, a law, and a
theory. |
|
Is there anything that can’t be tested by science?
Give an example of something where science wouldn’t work
What are the goals of science? |
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Scientific Methodology: The Heart of Science
The Scientific Method
A process used to arrive at an understanding and explanation
of observed phenomena; the way a scientific theory is produced
.
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Science is also trial and error, experimentation without
hypotheses and accidental discovery by well-prepared individuals.
.
Scientific methodology involves observing and asking
questions, making inferences, and forming hypotheses, conducting controlled
experiments, collecting and analyzing data, and drawing conclusions.
The Classical Version of the Scientific Method
1. Observation, or Collection of Data
Observation: A recorded phenomenon
2. Question
What could have caused the phenomenon observed?
Why did this phenomenon occur?
How could it have happened or how did it work?
.
Scientists use questions to make inferences.
.
Inference
A logical interpretation based on what scientists already
know.
3. Forming a Hypothesis
.
Hypothesis
A scientific explanation for a set of observations that
can be tested in ways that support or reject it.
.
A prediction of the consequences that would be observed
if the hypothesis was correct SUPPORTS a hypothesis.
.
If these consequences do not occur, the hypothesis may
not be correct and must be modified.
.
A useful hypothesis is one that can be tested and falsified—a
hypothesis is something that can be proven to not be true.
.
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If a hypothesis can NOT be proven false, then it can be used
as an explanation for the observed phenomenon.
.
Other Kinds of Support for Hypotheses
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Observation is another way of testing an hypothesis.
Some hypotheses cannot be tested by experiment, but can be verified by
direct observation (i.e.: astronomy).
-
Any scientific hypothesis or claim must be falsifiable,
or
open to negation through scientific inquiry. An hypothesis must be
put into a form where it can be proven to be false.
.
Example:
“UFOs are visiting the earth”
is not a scientific hypothesis,
because that statement cannot
be proven false.
4. Conducting Experiments
.
Experiment
Test to determine the validity of the hypothesis.
.
The results of the experiment should either confirm what
is predicted by the hypothesis or prove the hypothesis to be false.
.
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If the results of the experiment are different than what
was predicted by the hypothesis,
-
then the hypothesis is modified to explain both the original
data and the experimental results, and the process is repeated.
.
Experiments rely on keeping track of variables.
.
Variables
Things that can be changed
.
Examples of variables:
Temperature, light, time, nutrients
.
Controlled Experiment
An experiment in which only one variable is changed while
others remain stable, in order to determine which variable is responsible
for results observed.
.
Independent Variable (a.k.a.
Manipulated Variable)
The variable that is deliberately changed or manipulated.
.
Dependent Variable (a.k.a.
Responding Variable)
The observed variable that changes in response to the
independent variable.
.
Experiments typically contain both control and experimental
groups, which are replicated many times in order to obtain accurate data.
.
Control Groups
A group exposed to the same conditions as the experimental
group except for the independent variable
5. Collecting and Analyzing Data
The results of the experiments are data.
.
Quantitative Data
Data obtained by counting or measuring
.
Examples:
Number of organisms per area
Length, width, height, or weight
of an organism
.
Qualitative Data
Descriptive characteristics not obtained by counting
or measuring
.
Examples:
color, direction, shape
.
Research Tools
used for collecting and analyzing data
.
Examples
metersticks, calculators, scales,
graduated cylinders
.
Organizational Tools
charts, graphs, data tables
.
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Researchers must be careful to avoid errors in observations
and collection of data.
.
Sources of Error
-
Bias
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Inaccurate measurements
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Uncalibrated or incorrectly calibrated instruments
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Small sample sizes
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If the results of the experiment are different than what
was predicted by the hypothesis, if the hypothesis was not supported, then
a new or modified hypothesis is proposed to explain both the original data
and the experimental results, and the process is repeated.
6. Conclusion
The most simple general explanation that organizes the
hypothesis, predicted effects, and experimental findings.
7. Documentation, Verification & Confirmation
All the data, hypothesis, experiment & results, and
conclusions must then be published in a recognized scientific journal;
the data must be verified, the experiment must be able to be repeated and
the results confirmed.
8. Theory
An understanding of the world around us based on the
scientific method and confirmed by experiments.
What is the purpose of the Scientific
Method?
REVIEW & DO
NOW
Answer the following questions: |
| Define what is meant by the Scientific Method.
What are eight steps in the Scientific Method?
Distinguish between observation and data.
What is an inference?
What is a good definition of an hypothesis?
What are variables?
Give some examples of variables.
What is a controlled experiment?
What is the difference between an independent (or manipulated)
variable and a dependent (or responing) variable? |
|
| What is a control group?
What is the difference between quantitative and qualitative
data?
What are some tools a scientist might use in research
and data organization?
What are some sources of error that might yield erroneous
data?
What happens if the result of an experiment are not as
predicted?
Why is documentation, verification & confirmation
important in the development of scientific theory?
What is the difference between an hypothesis and a theory? |
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