Card Set Information
Scientific Method 9-23-12
What is scientific method?
Process of inquiry & experimentation to explore observations & ans questions
Used to seek cause & effect relationship in nature
What are 6 basic steps in scientific method?
Ask a question based on observation
Construct a hypothesis
Test hypothesis w/experiments
Analyze data & draw conclusion
When doing background research what should we be doing?
Learn about topic
Read about previous related studies
What is a hypothesis?
Testable educated guess about how things work
If _________, then __________ will happen
When designing experiments to test hypothesis we have to do what 2 things?
Decide what we are testing
How we are going to test it
What is a variable?
Any factor, trait or condition that can exist in differing amts or types
What are the 3 types of variables?
Describe the independent variable.
This is the 1 that is going to be changed by the scientist
Gd experiments only have 1
Describe the dependent variable.
This 1 is going to be unmanipulated JUST OBSERVED
There can be more than one
Changes in it are dependent upon the independent variable
Explain the controlled or constant variable.
MUST remain constant throughout experiment
ie # of cells, Data collection points, Environmental conds
What are ctrl groups?
Groups used for comparison to your experimental group
This grp gets no tx
2 types - pos & neg
Describe the pos ctrl grp.
Has a known effect on the dependent variable
Not always used
Describe the neg ctrl grp.
Complete absence of independent variable
For determination of significant changes in dependent variables
ALWAYS IN DESIGN
What is the triplicate rule in scientific method?
At least 3 experimental trials ensure reproducibility of results
What are the 2 types data useful to scientific experimentation?
Describe quantitative data.
Numerical measurement gained w/instruments
Can be measured, counted, have a numerical value
Describe qualitative data.
Subjective to interpretation
Photos & charts are good
How do we report quantitative data?
Statistical analysis to make sense of all the numbers
What is the confidence interval?
A narrow segment where most of your data should fall.
Expressed in a P-value
Explain the P-value.
This is the probability that you will fall within a 95% CI
If our data supports our hypothesis we should . . . .
Conduct more tests to refine
If our data does not support our hypothesis we should . . .
Report our results
Use it to form new hypothesis
Begin testing new hypothesis