Advanced issues in experimental research methods Flashcards
(47 cards)
What is a hypothesis?
A specific, testable claim or prediction about what you expect to observe given a set of circumstances.
It is a tentative statement about the assumed relationship between two (or more) variables.
What is the difference between a research hypothesis and a null hypothesis?
Research Hypothesis (H1): The statement you’re testing, what you expect to find. Null Hypothesis (H0): States that an effect is absent.
Research hypotheses can be directional (one-tailed) or nondirectional (two-tailed).
What do experiments allow researchers to test?
Causation.
Surveys allow testing for correlation.
What does correlation mean?
Two variables vary together – as one variable changes, the other variable tends to change as well.
What is spurious correlation?
A correlation that does not imply causation.
What are the key features of an experiment?
- Manipulates an independent variable (IV)
- Holds other variables constant
- Measures changes in dependent variable (DV)
What is an extraneous variable?
Anything other than the independent variable that could affect the dependent variable.
What is a confounding variable?
A type of extraneous variable that affects the dependent variable and varies with the independent variable in a systematic manner.
What is the difference between between-subjects and within-subjects designs?
Between-subjects: Each participant is tested in only one condition. Within-subjects: Each participant is tested in all conditions.
What is effect size?
A statistical measure of the magnitude of an observed effect in a population.
What is statistical power?
The probability of detecting a true effect when it actually exists in your population.
What is internal validity?
The extent to which we can be sure that the changes observed are caused by our manipulation, rather than other factors.
What are maturation effects?
Participants’ behavior changes naturally over time, unrelated to the treatment/intervention.
What is a control group?
A group where the independent variable is thought to have no influence, serving as a baseline.
What are the types of control groups?
- Passive: Participants do nothing or a meaningless task
- Active: Participants do something assumed to have no effect
- Wait list: Participants are waiting to take part in the intervention
What is differential attrition?
When people leave one condition or treatment more than any other, leading to biased data.
What are order effects?
Changes in behavior due to the order in which conditions are completed.
What is counterbalancing?
Testing different participants in different orders to minimize order effects.
What is a matched pairs design?
A design where participants are matched on a variable that correlates with both IV and DV.
What is participant reactivity?
Participants behave differently because they are aware of being tested or try to guess the experimenter’s expectations.
What is the 5% criterion in hypothesis testing?
It represents the probability of making a Type I error (α).
Fill in the blank: A hypothesis is a specific, testable claim or prediction about what you expect to observe given a set of _______.
[circumstances]
True or False: Correlation implies causation.
False.
What are order effects?
Order effects refer to the possibility that participants behave differently based on the order in which conditions are presented.
