PSYC1111 Study Guide - Final Guide: Ecological Validity, Louis Pasteur, External Validity
The “ietifi Method
Deisios, deisios…
• We are constantly faced with information and questions in all aspects of our lives
o Should I eat Paleo diet?
o How much does the soul weigh?
o A I silig eause I happ?
• How can we make informed decisions?
Scientific Thinking
• Think scientifically
• These questions require evidence
o Subjective opinions
• What type of evidence is required?
• How to evaluate the evidence?
o Statistics
o Methodology
Why should we care?
• Who stands out?
• Illusory correlations and stereotype formation (Hamilton and Gifford, 1976)
Assumptions of Science
• Determinism
o There is some underlying systematic order to many phenomena in the
universe
o If this was not true then you would never be able to identify a consistent
underlying cause/set of causes
• However; this can go too far! Not everything that happens must have unifying single
explanation
• Illusory correlations
Parsimony
• Oas razor
o When you have competing hypothesis that are equally good at predicting the
results, the hypothesis with the fewest assumptions should be selected
o Simpler explanations are better
o In extreme circumstances this is obvious
Empiricism
• Claims must be supported by evidence
• Hearsay and expert opinion are not good enough
• Physical/empirical evidence is necessary
• Not just any evidence, systematic and well collected evidence
• Extraordinary claims required extraordinary evidence
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o Carl Sagan
Testability
• Theories and hypotheses should be testable
o You should be able to device some test or observable event based on the
theory/hypothesis
o You should be able to put fourth some empiricism
• Operationalism: How to quantify (empirically) what you mean
o How do you measure weight?
o How do you measure learning?
o How do you measure hunger?
• Operationalising variables allo
• However, verifiability is not the only thing you should look for in a hypothesis/theory
• Unfalsifiable theories
o E.g. Freudian psychoanalysis
o A theor that eplais eerthig, eplais othig
The Scientific Method
• The sietifi ethod ill ot tell ou hat is true or hether soethig has ee
proe
o The scientific method is a process
o Nothing is set in stone, it can always be changed if new evidence compels us
to do so
• It is an interactive process
o Scientists discuss their ideas with other scientists and publish their work in
peer-reviewed journals
o Pulished ork is ot guarateed to e orret ut it has passed a uer
of checks to increase your confidence in its accuracy and meaning
• Good science should always be clear. Unnecessarily vague and unclear theories hide
vagueness, misunderstanding and are not useful.
Peer Review
• The system of scientific publishing is difficult and rigorous
• You dot tr to falsif our o fidigs ut the sste is desiged to fid as to
falsify your research
• You must produce good findings and have experts agree that the experiment is valid
Why trust science?
• It works
o In the past, the reliance on different non-systematic and metaphysical
approaches to understanding the world did not work
o For example, modern medicine
▪ The efficacy of modern medicine to prevent you from dying after
losing a limb
▪ Older traditions had limited success eg. Using herbs on wounds
• Wearing masks to block smells during the plagues
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▪ Attempts at treating people were mostly guesswork
▪ Modern germ theory – Louis Pasteur experimentally tested methods
of killing microorganisms
Pseudoscience
• What is pseudoscience?
o Astrology
o Phrenology
o Crystal healing
o Extra sensory perception
It must be that they have different aims!
• Aims of science
o Description
o Prediction
o Explanation
How do we differentiate science from pseudoscience?
• Methodology?
o Observations
o Relationships between variables
o Experiments
• Here is where the differences can arise
o Some pseudoscience uses scientific methodology and techniques
o Sometimes these are employed but poorly
• Pseudoscience does not change when sufficient evidence suggests that it is wrong
Two Main Factors
• So, the term pseudoscience does not refer to a different kind of research, it refers to
science and thinking that has been flawed and refuses to change
• Normally this involves one or both of these factors:
• Flawed/biased evidence – observations or experiments
• Resistance to change or let go of failed ideas/theories/hypotheses
Astrology
• Astrology is the ancient art of predicting future events in the world based on the
position of the stars and planets
• Horoscopes are readings of the position of the planets and stars at the time
of birth and using these to predict the personality and the future events of an
individual
• Theory: there is a causal relationship between astronomical phenomena and events
in the human world
• Common argument: the moon
• History: Astronomy and Astrology were intertwined until the 17th Century
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find more resources at oneclass.com
Document Summary
Scientific thinking: think scientifically, these questions require evidence, subjective opinions, what type of evidence is required, how to evaluate the evidence, statistics, methodology. Illusory correlations and stereotype formation (hamilton and gifford, 1976) Assumptions of science: determinism, there is some underlying systematic order to many phenomena in the universe. If this was not true then you would never be able to identify a consistent underlying cause/set of causes: however; this can go too far! Not everything that happens must have unifying single explanation. Parsimony: o(cid:272)(cid:272)a(cid:373)(cid:859)s razor, when you have competing hypothesis that are equally good at predicting the results, the hypothesis with the fewest assumptions should be selected, simpler explanations are better. Empiricism: claims must be supported by evidence, hearsay and expert opinion are not good enough, physical/empirical evidence is necessary, not just any evidence, systematic and well collected evidence, extraordinary claims required extraordinary evidence, carl sagan. Freudian psychoanalysis: a theor(cid:455) that (cid:862)e(cid:454)plai(cid:374)s(cid:863) e(cid:448)er(cid:455)thi(cid:374)g, e(cid:454)plai(cid:374)s (cid:374)othi(cid:374)g.
