McMaster PSYCH 1X03

anectodal evidence

Evidence from others or from personal experiences

Experiment

Tool used to measure the effect of the independent variable on the dependent variable

Within-Subject Design

In an experiment, each participant is their own control group. Repeat task while manipulating independent variable. Cons: Time consuming, costly, and Practice Effect

Practice Effect

Improvement of performance caused by experience, repetition and familiarity

Random Assignmnent

Randomly assigning participants to control or experiment groups to reduce bias

Sample

Group that represents population and participates in experiment

Population

General people we are learning about

Random Sample

Selecting participants from a population at random for an experiment to reduce bias

Confounding Variable

Variable other than the independent variable that affects results

Placebo Effect

Participants demonstrate a response unrelated to the therapeutic effect when they know what the expected results are

Participant Bias

Actions by the participant that effect results, not including the independent variable

Experimenter Bias

Actions by the experimenter that promotes the results they hope to see thus causing inaccurate results

Double-Blind Study

When neither the experimenter nor the participants know what group the participants are a part of (experiment or control)

descriptive statistics

Way of presenting data that instantly describes the general idea of results

Histogram

Graph that shows frequency of each data point in a set of data

Frequency Distribution

Graph that shows the distribution of how frequently each value appears in a set of data. Derived from histogram

Normal Distribution

Symmetrical bell curve with one peak

Measures of Variability

Tell us how spread out data points are

Standard Deviation

Unit of measuring the average of each point from the mean. Smaller=Data points are concentrated towards the peak

inferential statistics

Statistics/results that allow for interpretation and inferences to be made about the population the sample represents

T-Test

Test that determines the probability that the two samples (group and experimental) were drawn from the same population therefore difference between data points were derived by chance

P-Value

T-tests's unit of measurement to determine whether difference between data point is large enough to make claim. <5% = Less than 5% probability to gain data by chance therefore significant.

Statistical Significant

Difference between groups are truly caused by manipulated variable rather than chance/random variation (P value <5%)

Observational/Correlation Studies

Form of data collection to avoid unethical experimentation. Observe variables without performing explicit manipulation

Correlation

A measure of the strength and direction of the relationship between two variables or data sets.

Correlation Coefficient. +1 , -1, 0

Value that tells us the strength and direction of a correlation. +1: Both increase, -1: As one increase the other decreases, 0= weak correlation

operational definition

a statement of the procedures (operations) used to define research variables. For example, human intelligence may be operationally defined as what an intelligence test measures. Specifies vague concepts

Constructs

theoretical idea that is useful for describing a general concept but difficult to measure in practice. E.g. Intelligence

Levels/Methods of Analysis

Different perspectives to research questions. Includes learning, cognition, social development, evolution and neuroscience. Research ideally applies a multi-level approach

Parsimony

When there are competing explanations, pick the explanation with the least number of untested assumptions. pillar of the scientific method

Natural Order

Behavior can be explained by underlying mechanisms for all people. pillar of the scientific method

Generalizability

Cause and effect found in a lab can also be produced in everyday life. Criticized pillar of the scientific method

Conservatism

Support current explanation until new fats accumulate that the current explanation cant deal with

Empircism

Knowledge should be based on both actual observation and research

Prediction

Theory that cannot be tested

Reliability

Ability of a test to yield very similar scores for the same individual over repeated testings

Validity

the extent to which a test measures or predicts what it is supposed to

Third Variable Problem

correlation does not equal causation

Binary Variable

Variable with only 2 possible values

Case Study pros and cons

Pros: In depth info, clear evidence for unusual cases. Cons: Not generalizable, subjective

Direct Observation pros and cons

Pros: Decrease artificial environment, long period of time. Cons: Hard for observers to go unnoticed, biased responses and interpretations

Experiment pros and cons

pros: Strict control, high accuracy. Cons: Artificial environment, hard to translate to real world, ethical and moral limits

measures of central tendency

mean, median, mode

Mean Cons

vulnerable to outliers

Mode Pros

Applicable to non-numerical values

Type 1 error

Claiming the IV manipulation had an effect when difference is actually the result of sampling error. Error is in the same direction as prediction

Type 2 error

Sampling error causes an effect opposite as prediction. Caught by replication

social desirability bias

A tendency to give socially approved answers to questions about oneself.

response set

a tendency to respond to questions in a particular way that is unrelated to the content of the questions

instrumental/operant conditioning

type of learning in which a behavioral response can be conditioned through reinforcement. Learning contingency between behavior and consequence

Thorndike

Performed Cat in a puzzle box experiment. Developed concept of refinement of behavior (stamped in, stamped out, and law of effect)

Law of Effect

Behavior resulting is positive reinforcements are stamped in

Reinforcer

A stimulus/consequence that changes the rate of response when presented after the response (can be positive or negative)

Reward Training

Presentation of a positive reinforcer to increase behavior

Omission Training

The removal of a positive reinforcement following a behaviour to decrease the frequency of that behaviour.

Escape Training

Removal of a negative reinforcer to increase behaviour

Punishment Training

presentation of a negative reinforcer after a response in order to decrease behavior

Cumulative Recorder

Graphic recorder that demonstrates rate of behavior/pattern of acquisition. Records response rate, time between responses

Autoshaping

Type of IC. Does not require guidance

Shaping

Type of IC. Requires guidance as behavior is complex

discriminative stimulus

Stimulus that individuates whether contingency is valid. SD+ = Valid

Continuous Reinforcement

Response is presented with reinforcer each trial

Partial Reinforcement

Response is presented with reinforcer sometimes

Ratio Response

Form of Partial Reinforcement. Reinforcer is presented based on the number of responses

Interval TIme

Form of Partial Reinforcement. Reinforcer is presented based on time since last reinforer was presented

Fixed Constant

Subcategory of interval and ratio schedules. Ratio and time reached has no exceptions

Variable Ratio/Interval Scale

Subcategory of interval and ratio schedules. Presentation of reinforcement is based on a variable ratio or time (average)

Fixed Ratio Schedule

Reinforcement is always given following a specific number of responses. Pause-and-run pattern

Fixed Interval Schedule

Reinforcement is always given at a specific time. Scalloped graph

Variable ratio schedule

Reinforcement is given following an average number of responses. Straight line up. VR-10 is more steep than VR-40. More robust

Variable interval schedule

Reinforcement is given following an average time. Response is continuous and steeper with shorter times. Doesn't want to miss opportunity for reinforcement

Operant

Behavior that directly causes a +ve or -ve consequence

Primary Reinforcer

Biologically beneficial reinforcer

Secondary Reinforcer

Come to reinforcing through previous learning

Operant Chamber

Chamber with mechanism by which an animal could respond to produce a reinforcer. Better than puzzle box

Delay of gratification

Ability to tolerate waiting for the +ve reinforcer

Testing Effect

Learning is better facilitated through difficult testing and feedback

Chaining

Teaching a complex behavior by reinforcing with the opportunity to perform the next response

Contrast effect

Changes in the value of a reward to shift response rate. -ve contrast: Decrease response reate

Overjustification effect

Newly introduced rewards for a previously unrewarded task can alter an individual's perception

Post-reinforcement pause

Occurs in FR schedule. Organism stops responding before starting again

Ratio Strain

Occurs in FR schedule. Longer pause of response as ratio for reinforcement increases (500 pecks by a bird for seed)

Break point

Occurs in FR schedule. Stopped response as ratio for reinforcement increases (500 pecks by a bird for seed)

Mirror neurons

cells that respond in the same way when performing an action as it does when the animal processing the cell observes someone else perform the action

Unconditioned Stimulus

Stimuli that automatically elicits a response without training

Unconditioned Response

Automatic reflex to a stimulus. Biological reflex. Affected by habituation or sensitization

Conditioned Stimulus

Originally neutral stimulus that becomes associated with the US. Presence of CS predicts the upcoming of the US. Occurs before the US. Acquisition between US and CS. Now causes response

Conditioned Response

Response to CS. Similar to UR

Acquisition

The learning of a contingency between a US and CS. Speed of acquisition can be fast or slow. Negatively accelerating curve

Ivan Pavlov

Noticed salivation in dogs when metronome was activated

Conditional Reflex

Trained reflex

Contingent relationship/Contingencies

One stimuli reliable predicts the presentation of another

Unconscious learning

Composed of Classical conditioning and Instrumental conditioning

Extinction

The loss of CR when the CS no longer predicts the US. Inhibitory response competes with previously learned contingency

Spontaneous Recovery

The reemergence of the CR with the presentation of the CS following a rest period after extinction

Stimulus Generalization

The ability for a range of similar CS to elicit the CR. Makes classical conditioning for efficient and flexible

Stimulus Discrimination

Restricts range of stimuli that can elicit response as stimuli that are too different from the CS do not accurately predict the presence of the US. Causes a flattened graph

CS+ (Excitory conditioning)

Stimuli that predicts the presence of the US. If a CS- is also present, intermediate response will occur

CS- (inhibitory conditioning)

Stimuli that predicts the absence of the US. Refines learning process. If a CS+ is also present, intermediate response will occur

Phobia

Exaggerated, intense fear of ___.