Critical Thinking PSYC1102 Lecture Info

Theory (textbook def)

A set of formal statements that explains relationships between phenomena

Characteristics of theories

- Derived from empirical evidence

- Used to generate hypotheses which are tested via experiments

Scientific explanations of Kitty Genovese case study: why don't people help?

- Apathy (personality trait)

- Depends on social situation

Example of theory, explanation + application

Diffusion of responsibility

- Responsibility of individual is shared between witnesses

- Possible derived hypothesis: more witnesses -> more diffusion of responsibility + thus people less likely to help

Descriptive research def + example

- Aims to describe a phenomenon without manipulating it

- E.g. crime stats

Correlational research def + example

- Examines relationships between two or more variables without manipulating them

- E.g. correlation between SES and longevity

Correlational patterns (3)

- Range from -1 to 1

- Positive or negative

- Perfect correlation (1) usually doesn't occur in real world

Correlational strength (Cohen) (3)

- Small (.1)

- Medium (.3)

- Large (.5)

Effect size

Whether a relationship between variables is meaningful or not

Notes on drawing causal inferences

- Correlation ≠ causation

- Could be unrelated, 3rd variable or bidirectional (in which case causation is present)

- The higher the sample size, the more representative

Quasi experiments (3)

- Participants allocated to different experimental conditions on non-random basis

- Often used in every settings (e.g. SES study)

- Researcher has little control

True-randomised experiments

- Participants are allocated to different experiment conditions on random basis

- E.g. first person to do experiment is in condition A, second is in condition B etc.

Experiments test...

- Cause and effect relationships