Week 1 Flashcards
Describe empiricism
Knowledge can only be acquired through observation and experiences
Describe the scientific method
A set of of principles about the appropriate relationship between ideas and evidence.
Theory
An hypothetical explanation of a natural phenomenon
Hypothesis
A falsifiable prediction made by a theory
What are the three things that make people hard to study
- Reactivity
- Complexity
- Relativity
What is an operational definition
What we are measuring and how we will measure it. Important for measurement of observations
Validity
The extent to which a measurement and property are related (eg. Do IQ tests measure intelegence)
Reliability
The tendency for a measure to produce the same measurement when done again
Describe demand characteristics and ways to reduce them
Aspects of an observational environmental environment that cause people to react in a certain way that threatens the validity of a study. Ways to avoid this involves
1) Cover stories- False leading stories about what is being studied
2) The unrelated experiments-Having two experiments, one with the variable and one without
3) Use of nonreactive measures-Participants don’t know what’s being measured
Naturalistic observation
A technique for gathering info by unobtrusively observing people in their natural habitats
Observer/Researcher bias
Researchers results being affected because they see what they want to see
Double blind experiment
Neither the researcher nor the participant knows the true purpose of an experiment
Frequency distribution
A graphical representation of measurements arranged by the number of times each measurement was mad
What are descriptions
Graphical representations and statistics (mode, median, mean)
What are the three methods of research
Descriptive research, Correlational studies, Experimental methods
Describe case studies
In depth analysis of an individual, group, or event.
What are some advantages of case studies
- Challenges validity of theories
- Can illustrate effectiveness of programs for special populations
- Useful for studying rare phenomenon
- Source for new ideas
What are some disadvantages of case studies
-Researcher bias
-Does not establish cause-effect
Generalizability questionable
Why is a representative sample important
Because you cannot study the whole population, your sample must reflect important characteristics of a population, and random sampling must be used
What are surveys and what are some drawbacks
Questionnaires asked to people. If they are given to unrepresentative populations, this can lead to faulty generalizations. Surveys also rely on self-reports which can be faulty, and cannot draw cause-effect relationships
Bimodal distribution
Has two areas of peak frequencies. (eg. one group got high scores for attending a lecture, while one got low scores)
What’s the difference between normal and skewed distribution
Normal distribution has a mean equal to the median. The mean is affected in skewed results and it is higher than the median if the results are positively skewed, and lower if the results are negatively skewed
How does skewed distribution affect what measure of central tendency is used
Normally, mean is used, but when a distribution is skewed the median is used
Name the two measures of dispersion
- Range- The largest measurement minus the smallest measurement
- Standard deviation- The difference between the measurements in a frequency and the mean of that distribution
Percentile rank
The percentage of scores that are equal to a score or lower
Standardized score
A score expressed by the number of standard deviations that the original score is from the mean
What is a variable
A property whose values can vary across individuals or over time
What is a scatterplot and it’s purpose
Each pair of scores is illustrated by a point on a graph, illustration the relationships between two variables
Describe correlation
Two variables are correlated when a difference in one is synchronized with a difference in another. The correlation constant is (r) and the values fall from-1 to 1, with higher correlation being when the number is farther away from 0
Give an example of a correlational study
Correlation constant between studying on a test and test score is 0.8, meaning there is a high correlation, while the correlation between height and test score is -0.05, meaning there’s little to no correlation.
What does the slope tell about the strength of a relationship
The higher the slope, the stronger the relationship.
Why can’t cause and effect relationships be determined from correlational studies
- Neither variable is given a control group
- Other explanations may be possible such as the causal relationship working in the opposite direction or both directions, or a third variable being present
Natural correlations
The correlations we observe in the real world
Third-variable correlation
Two variables are correlated because they are related to a third variable.
Matched samples
A technique where the third variable is kept constant among participants
Matched pairs
A technique where each participant is identical to others in terms of a third variable
What is an experiment
A technique that establishes a cause-effect relationship between two variables. The two main features are manipulation and random assignment
Independent vs dependent
Independent is changed while dependent changes because of the independent and is measures
Experimental vs control group
Experimental group is treated in a certain way while the control group isn’t treated in any way. Some experiments have no control groups
How do you conduct an experiment
Manipulate the independent variable while measuring the dependent and keeping others constant. Thus, the change in the dependent is caused by the change in the dependent.
Describe within-subject design
Using one participant for a study that has greater statistical power and economy of participants but can have carryover, practice, and fatigue in the participants
Why is random assignment important
Having random assignment ensures that what variable a participant gets isn’t based on a third variable
What is self-selection
Allowing participants to select what variable they get, this can cause bias
Between subject design
Different conditions are applied to different groups and should be used if the disadvantages of within subject design is unavoidable
What are inferential statistics
Procedures for calculating the chance that results were obtained on chance alone
How does a probability become statistically significant
If the value is less than 0.05 (probability (p) is the likelihood random assignment failed in an experiment)
What is statistical significance and what is an issue with it
Statistical significance tells us the result did not come by chance but it does not have practical use (eg. a drug makes you lose 0.01 of a pound which is statistically significant but not practically)
How can a result be significant
If a real statistical relationship exists, then it is significant but it could also be insignificant at the same time
Is random variability avoidable
No, it is inevitable
Describe bias
Non-random variation caused by some factors
Describe population, sample, and sampling bias
Population is the complete set of possible participants, sample is a partial collection drawn from the population, and sampling bias is when the sample is not representative of the population
Internal and external validity
Internal validity is the extent to which we can trust the conclusions we have made and external validity is out ability to generalize an experiment beyond its original settings
American Psychological Association
Established a set of ethical rules researchers must follow in order to publish anything
What are some ethical guidlines
Respect for human dignity and respect for free and informed consent.
What are the guidelines of an experiment
Minimize harm and maximize benefit, have respect for vulnerable people and make sure they are protected, respect privacy and confidentiality
What is a debriefing
A verbal description psychologists provide to participants after an experiment is done about the true purpose of the experiment
