L04: Methods Flashcards
Braintenberg Vehicles
Machines with a very simple internal structure that were then studied as if they were animals in a natural environment to describe their behaviour.
Ockham’s Razor
Given several explanations for a phenomenon, the most simple one should be accepted.
Reductionism & Its limits
Describing things in terms of simpler phenomena.
Problem: Very complex behaviour can arise from a small set of simple principles. Simple explanations are easier to test.
Rationalism
Observation is not only unnecessary but potentially misleading.
Empiricism
Hypothesis & theories need to be confirmed by observation
Scientific Method
- Make observations
- Ask how/why
- Form hypothesis
- Use hypothesis for prediction
- Run experiment
- Analyze outcomes
- Report results
- Hypothesis proven/disproven
Inductivism
Several observations are used to induce theories, which are used to deduce hypothesis, eventually leading to laws.
Falsification
Tests are designed to refute the predictions, not to confirm a theory. If the prediction is falsified, the theory is wrong.
Kuhn’s Scientific Process (Constructivism)
Paradigm Shift
random fact gathering > puzzle solving research > anomaly > crisis > revolution
Observer Effects
Include: experimenter bias, demand characteristics, representativeness, and artificiality
Experimenter Bias
The experimenter may subconsciously affect the behaviour of the participants
Demand Characteristics
The person being studied might engage in the experiment actively, leading participants to respond in a way to confirm the assumed hypothesis and please the experimenter.
Milgram Experiment
Participants were willing to give a fatal shock to an innocent person because they were instructed to do so by the experimenter (demonstrates demand characteristics)
Representativeness
Psych research should be representative of the human population
Artificiality
Psych research often unfolds inside research labs, where participants are subjected to bizarre, reductionist tasks.
Descriptive Methods
Based on observation and case studies
Naturalistic observation
Psychologists observe the behaviours of people/animals in their every day environments to avoid interfering with usual behaviour.
Hawthorne Effect
Being observed can lead participants to change their behaviour to make a good impression
Hawthorne Experiment
Productivity increased when people were being observed
Reactivity
Individuals alter their performance or behavior due to the awareness that they are being observed
Expectancy Effect
Experimenters’ expectations cause them to give off subtle cues that change behaviour
Expectancy Effect Experiment
Rats trained by students who believed their rats were bred to be fast did the task quicker.
Response Bias
Tendency to answer survey questions incorrectly for various reasons.
Correleation Studies
Explore how variables are naturally related, but cannot detect causal relationships
Directionality Problem
Direction of the relationship can appear ambiguous. Causation cannot be inferred
Positive Correlation
as x increases y increases
Negative Correlation
as x increases y decreases
Zero Correlation
variables aren’t related
Third Variable
Relationship may be depending on a third, not measured variable
Independent Variable
Is manipulated
Dependent Variable
Affected by the manipulation
Confounding Variable
Influences the IV but is not controlled in the experiment
Cause and effect relationship
Requires rigorous control to confirm this relationship
Experimental Groups
IV is manipulated
Control Group
The standard to which comparisons are made in an experiment (IV is left as is)
Experimental Hypothesis
Any differences are due to a variable controlled in the experiment
Internal Validity
Study is well-designed and free from biases or confounds
External Validity
How well the outcome of a study can be expected to apply to other settings
Descriptive Stats
Way to organize, summarize, and generally describe raw data.
Sample
A subset of the larger population we are interested in
Population
A large pool of individuals from which a sample is drawn.
Sampling Error
error in a statistical analysis arising from the unrepresentativeness of the sample taken
Frequency Distribution
Also known as a histogram. Provides a picture of how the data is distributed across the range of possible values
Central tendency
descriptive summary of a dataset through a single value that reflects the center of the data distribution
Mean, median, and mode
Mode
The value that occurs most often in a dataset
Median
Corresponds to the 50th percentile
Mean
The average value in a dataset
Normal Distribution
Symmetrical and bell shaped curve where the mean, median, and mode are the same. (ex. IQ scores)
Variability
Degree of spread in the distribution
Standard Deviation
The average distance of all data points from the mean
Statistically Significant
Said to occur when the probability that the observed findings are due to chance is very low (less than 5%)
