Experimental Methods Flashcards
Intuition
Internal way of knowing where” you just know” something
Problems w/ Intuition
individual; collaborating on knowledge = difficult
Observation
An Internal & External way of knowing; knowing through experiences
Problems w/ Observation? (4)
pure observation is difficult
1. Not always possible; limited (can’t see everything)
2. Not always true (room for misinterpretations) e.g. illusions
3. Observation can change over time
4. People disagree on their experiences (issues w/ consensus)
Combatting Issues of Observation (Impossibility, Reliability, Biases & Opinion Differences)
- Impossibility –> technological tools/advancements
- reliability –> openness, falsifiable hypothesis, double-blind experiments
- biases & opinion differences –> scientific skepticism, peer review, replication
Technological Tools/Advancements
Tools to help measure/observe;
Combats impossibility of observation; development/advancements allow humans to observe things that once weren’t able to be observed
Openness (& Observation)
All data should be publicly available;
Combats reliability of observation; Allow others to decide whether its reliable or not
Double-Blind Experiements
Experiments where neither participant or data collector is aware of the hypothesis;
Combats reliability of observation; Minimizes expectancy bias
Scientific Skepticism
Not believing theories/observations to be true;
Combats bias & opinion differences
Peer Review
Having conclusions reviewed by other scientists; double checking work
Combats bias & opinion differences;
Replication
Study/Experiments is replicated to see if the same results are found;
Combats bias & opinion differences; accumulation of confirmed/disconfirmed hypotheses
Scientific Method
- Hypothesis
- Operationalize
- Measure
- Analyze
- Report
Problems w/ the scientific method
Problems: designed & validated by established scientists, scientism*, science is generalizable – how does it apply individually?
Scientism
the belief that knowledge can only be derived through science
Hypothesis
a prediction. derived from a theory, about what should happen in a scientific study
Confirmatory Studies
Start with a falsifiable hypothesis & then find data that either confirms/disconfirms
Exploratory Studies
Start by collecting data without a strong hypothesis & then look for patterns to come up with a theory
Operational Definition
a description of a psychological property in measure, observable terms; redefining concept into smth measurable
Measure
measuring
Instrument
anything that measures the operational definition
Validity
Actually measures what it claims to measure
Reliability
Gives similar measurements each time it is used
Power/Sensitivity
Can detect small differences in the measure
Analyze
To make sense of the data
Descriptive Statistics
Mathematical tools used to summarize data into ways of understanding it (e.g. mean, variability, range)
Inferential Statistics
Mathematical tools used to help us decide if the data confirm or disconfirm some hypothesis (statistical significance)
Report
Way in which researchers present their findings/results
Peer Review
Process through which scientists receive feedback about their work from other scientists in the field
Role of Peer Reviewers
To be skeptical of claims to identify alternative explanations, assess instruments for validity, reliability and power/sensitivity, and double-check the statistics
Study Designs/Methods (4)
A set of guidelines for how data is collected for a study
1. Naturalistic Observation
2. Case-Studies
3. Correlational Studies.
4. Experiments.
Naturalistic Observation
A type of study design/method; x
Problems w/ Naturalistic Observation
x
Case-Studies/Case-Methods
A type of study design/method; x
Problems w/ Case-Studies/Methods
x
Correlational Studies
A type of study design/method; Estimate the numerical relationship/prediction between two measured variables
Steps for correlational studies
- Choose any two variables.
- Measure the two variables with an instrument in as many people as possible.
- Graph the relationship for all collected data.
- Estimate the “direction” and “strength” of the correlation.
Positive Correlation
As one variable increases, the second increases as well
No Correlation
There is no correlation between the two variables
Negative Correlation
As one variable increases, the second decreases
Correlation vs Causation
A correlation between two variables does not imply that one variable caused the other
(Potential) Reasons for why correlation does not equal causation (3)
- Directionality Problem
- Third Variable Problem
- Spurious Correlations
Directionality Problem
For any correlation, A might have caused B, or B might have caused A
Third Variable Problem
AKA: Confound Variables; For any correlation, a third, unmeasured variable may be the true cause of the measured ones
Spurious Correlation
Strongly correlated variables that we know are not casually related
Experiments
A type of study design/method; A study design where one variable (of interest) is manipulated/changed to see its casual effect on another (in a controlled environment)
Key Components of Experiments (4)
Four Key Components of Experiments:
1. Independent variable
2. Dependent variable
3. Random Assignment
4. Random Selection
Independent Variable
The variable manipulated (experimental vs control group)
Dependent Variable
The variable measured
Random Assignment
Participants are put into the experimental/control group randomly
Random Selection
Participants should be representative of population as a whole
