T1 - the scientific method Flashcards
What is the definition of science?
The systematic study of the structure and behaviour of the physical and natural world through observation and experimentation
What is the definition of biology?
The science of life
What is the scientfic method
An approach to knowledge acquisition that seeks to ensure our understanding is not shaped by personal beliefs/biases
Based on evidence
What are the 2 types of science?
Descriptive: characterizing patterns, describing systems (describing the physical/natural world)
Hypothesis-testing: testing one of more causal explanations for an existing pattern (explaining observations of the physical/natural world)
Why are the 2 types of sciences each important to the scientific method?
Descriptive - provides the grist for the hypothesis testinng method (provides the patterns and may suggest possible explanations)
Hypothesis testing - interprets patterns and in doing so provides the direction as to where to look for other patterns
What is induction in reference to the scientific method?
Specific observations (patterns) are synthesized to produce a general statement or conclusion (particular to general)
However even if all axioms are true, the conclusion might not necessarily be true
Generalizations rather than specifics
What is typically the source of biological hypotheses?
Induction - but this is not idea to test them
What is an example of induction ?
Assuming that because this bird is a swan and it is white and another swan exhibits the same characteristics
The generalization is made that all swans are white
What is deduction used for in hypothesis testing science?
Deduction is used to derive predictions and hence test hypotheses
What is a hypothesis vs a prediction?
Hypothesis = a causal explanation for a given pattern
Prediction = statement of what will be observed under specific conditions if the hypothesis is true
A prediction only exists within the context of a hypothesis and a particular study
What is an example of deduction?
Can be represented by a syllogism (if…then statements);
Premise 1: All birds have feathers
Premise 2: All robins are birds
Deduction = Therefore, all robins have feathers
What is deduction in reference to the scientific method?
Form of reasoning from one or more general statements (premises) to a logical conclusion
Unlike induction there is no uncertainty; if the premises are true then the conclusion necessarily follows
wrt testing a scientific hypothesis, predictions must follow deductively from hypotheses
What makes a scientific hypothesis?
In addition to being causal, all scientific hypotheses must also be refutable
A refutable hypothesis is one in which there are possible outcomes that are inconsistent with it
What is an example of a falsifiable (refutable) scientific hypothesis?
“All lions are black”
This statement can be falsifiable if we can find at least one lion to prove this statement wrong.
Can you prove a hypothesis? Why or why not?
Sir Karl Popper argued that science best proceedsby eliminating hypotheses, not by proving them
B/c, you cannot prove a hypothesis
What is a logical fallacy? Give a general example
If H then P, P observed, therefore H is true
- Humidity is high because it rained last night (H)
- If it rained last night the garden will be wet (P)
- The garden is wet (P observed)
- Therefore, the high humidity is due to the rain last night
This argument is invalid because the conclusion could be incorrect even if P follows deductively from H and then P is observed
This is because H is not the only potential cause of P (observing P may support H, but not prove it)
What are the 2 types of study?
1) Observational - researcher observes/measures/characterizes a system but does not alter it
2) Manipulative - (an experiment), the researcher changes something and compares what happens to a control (unmanipulated) treatment
The type is study is independent ofthe type of science
What are examples of the 2 types of studies?
1) Observational - observing the phosphorus concentration (taking measurements)
2) Adding phosphorus into half a lake and not the other and comparing the two results
What is inferential strength? Which study has a higher inferential strength than the other? Why is that the case?
A measure of how strongly the results support the conclusions
Manipulative studies have greater inferential strength than observation studies
- This is because manipulative studies better control for confounding variables
What are confounding variables?
A separate and often unknown variabel that may be responsible for the observed pattern
What is extrapolation?
Inferencing from the results of studies on model systems means that we assume that the model system behaves similarly to the actual system of interest
Model system = smaller in scale/simplified compared to the system of interest (models of the human body with similar body cells or structures)
The more extrapolation there is, the lower the inferential strength (less room for error)
What is statistical hypothesis testing?
Understanding if the pattern in the results is real
- Is it the result of chance? Random sampling variation? Or is it actually a repeatable biological phenomenon?
What are the 4 characteristics researchers require to be for knowledge acquisition?
1) Rational - to employ the scientific method
2) Skeptical - to seek to repeatedly and carefully scrutinize patterns and hypotheses, being willing to reject or modify hypotheses based on the evidence
3) Objective - being unbiased by preconceived notions, beliefs, ideologies…
4) Methodologicaly materialistic - restrict assumptions and explanations to the material world -> we dont consider the supernatural
What is science vs pseudo-science?
Pseudo = studies that seek only to confirm beliefs
- These are often not skeptical, rational or objective (they want the hypothesis to be true and don’t seek to reject it)
Note: Just because one piece of evidence proves the hypothesis does not mean ALL evidence supports it
What is a hypothesis vs a theory?
Theory = a hypothesis that has survived many attempts at falsification
Scientific theory = explanation of some aspect of the natural/physical world that has been repeatedly tested via scientific method
- when evidence is so overwhelming that we consider it fact
