PSYC105 Lecture Notes - Lecture 7: Ad Hominem, Texas Sharpshooter Fallacy, Begging
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PSYCH105 - CRITICAL THINKING IN PSYCHOLOGY
Wk. 7 – Reading Critically and Casual Relationships
Causal relationships
3 conditions for causality
Selection bias
Causes and effects as complex patterns
Reasoning critically
Inductive reasoning
Reasoning in psychological research
Fallacious reasoning
Fallacies of false generalization
Fallacies of relevance
Casual Relationships
What events cause other events to occur? E.g. X causes Y
Need sufficient evidence to conclude causality
Alternative explanations
Y causes X
Z causes X and Y
Simply correlation – merely a relationship between X and Y
Correlation does not imply causation
Goal
Figure out why something happened or how it came about
Why
Predict what will happen in the future
Form the basis of our decisions
Three Conditions for Causality
To show one event causes another to occur (i.e., X causes Y) 3 conditions
must be met
X and Y must be correlated
X must precede Y in time
All other factors (Z) must be ruled out
A causal relationship for which no real evidence exists
X Must Precede Y in Time
Assuming that because two things occurred close in time to one another,
the first event caused the second
Directionality problem
Does X cause Y or does Y cause X?
E.g. does self esteem determine academic achievement or vice
versa
find more resources at oneclass.com
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Third Variable Problem
Does an outside or third factor Z cause both X and Y?
E.g. intelligence causes self-esteem and academic achievement?
Can you eliminate all ‘third’ variables?
Selection Bias
Participant Variables
Biological, behavioural, psychological characteristics e.g. personality
traits
Environmental Variables
E.g. place of residence
Selection bias occurs when participant variables leads to selection of a particular
environment
Increases chance of finding a spurious correlation between participant
variables and environmental variables
Problem: self-selection in clinical trials
Need random sampling and random assignment
Casual Chains
Causes and effects usually appear as parts of more complex patterns, or a
casual chain.
Situation in which one thing leads to another, which then leads to
another, and so on.
Which cause is the real cause
Contributory Causes
A number of causes can also act simultaneously to produce an effect
Each cause contributes to the final effect
Interactive Causes
Causes
Rarely operate in isolation
Influence (and are influenced by) other factors
Interactive Causes
Reciprocal influences
Reasoning Critically
Deductive Reasoning
Reasoning from premises (i.e. reasons) known or assumed to be true to a
conclusion that follows necessarily from these premises
Deductive reasoning moves down from known general reasons to specific
facts. I.e. top-down approach.
Inductive Reasoning
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Simply correlation merely a relationship between x and y. Figure out why something happened or how it came about. Predict what will happen in the future. To show one event causes another to occur (i. e. , x causes y) 3 conditions must be met. All other factors (z) must be ruled out. A causal relationship for which no real evidence exists. Assuming that because two things occurred close in time to one another, the first event caused the second. E. g. does self esteem determine academic achievement or vice versa. Biological, behavioural, psychological characteristics e. g. personality traits. Selection bias occurs when participant variables leads to selection of a particular environment. Increases chance of finding a spurious correlation between participant variables and environmental variables. Causes and effects usually appear as parts of more complex patterns, or a casual chain. Situation in which one thing leads to another, which then leads to another, and so on.
