Scientific Methods
Not 1 specific formula 
I. Hypothetical – Deductive Method
many hypothesis (ideas),
eliminate those without data to support them
actual experiment(s)
II. Correlation Method
multi variable situations
Use statistics and computer models to
compare data to situations
ex: predict the weather
Very common
Steps in (a) Scientific Method (Hypothetical – deductive)
Used more like a flow chart than a list
1. Observation
Curiosity, skepticism, senses/ observations, experiences
2. Question
“Why? , How? , What if? “
3. Research
background information , look for an answer, list all
possible explanations, what you already know
4. Hypothesis
“If – then – therefore” statement, cause and effect,
educated guess, prediction, testable/ measurable,
“explanation on trial”… claims and statements
Scientific method continued
5.
Design an Experiment
Independent variable – “manipulated variable”
I/ the scientist manipulate or investigate,
only 1, the “IF”..,
what is being tested/varied/modified/changed by the researcher,
x axis
Dependent variable – “responding variable”
depends on what I did (independent)… plant is TALLER because
of the fertilizer,
“Then”, what is measured/changes, y axis
Controls –
everything you keep the same so that there is only one
independent variable., comparison/ base line, ‘control group’
Scientific method continued
6.
Collect data (during and after experiment)
numbers and units – quantitative data (quantity or amount),
descriptions = qualitative data (quality of something)
7. Analyze data
Put into tables, charts, graphs, look for TRENDS and correlations between
Ind.V and Dep. V., relationships. Show work, calculations and formulas
Either verify or falsify your claim with these steps– retest, restart, restate,
re-evaluate … ask more questions and do it again…. LOOPS !
8. Conclusion
Does your data show support for your prediction…. Accept Hypothesis or
declare Null Hypothesis. Explain what happened, what your results
were and where you could improve/change (error analysis is statistical
work done to show the precision of your measurements)
Do not say “Prove” – you didn’t prove 100% forever, you supported or
eliminated, until there is new evidence
9. Repeat/ report/ publish
Lab report or publication – grant money, peer review, share results, more
testing, etc.
Assignment – this may be done individually or in
collaboration with a partner (BOTH write and submit)
 1. on a sheet of plain paper (or your
iPad) create a flow chart version of the
steps usually covered in any scientific What was the
hypothesis or
experiment.
claim?
Set up/ control
 2. Read page 29 - 31 and list the
group, procedure
steps taken by Rita Colwell to verify or
Independent
correlate that water temperature is an variable,
indicator of cholera risk. (Might loop)
dependent variable,
data or results,
 3. Choose an article from the red
Conclusion/
folders provided and list the steps
eliminate or support
taken during a classic experiment
(Redi, Lister, Pasteur, Jenner, etc)