Chapter 2: Foundations of research Flashcards
(30 cards)
Variables vs constants
Varaiables: something that varies, meaning that it has at least two levels or values
If all participants are the same (fa. male), we keep ‘gender’ consistent
We use constants to check the effect on variables
Independent vs dependent variables
Independent: the kind of variable researchers manipulate
Dependent: depends on the values of the independent variable and shows it’s effect
Measured vs manipulated variables
Example: if we observe if people choose to have treatment for a disease or not (without us doing anything), we measure/observe the influence of nature, we manipulate it and see what changes
Conceptual vs operational variables
Conceptual: abstract concepts
Operational: choices that you make as a researcher to make the abstract thing researchable or able to manipulate
Studies make three types of claims
- Frequency claims
- Association claims
- Causal claims
Frequency claims
Say something about a frequency or a prevalence
Also associated with research called ‘descriptive research’
Each claim is about one variable that is measured (however, one study can make multiple frequency claims about multiple variables)
Association claims
Talk about relationships between two or more variables
Also called ‘correlational research’ (doesn’t mean we always use correlations to explain associations)
Correlations can be used for causal claims, but not all correlations are causations!
Types of associations: positive vs negative, linear vs curvilinear, absent (null effect)
Causal claims
Also talk about relationships between two variables, but here it’s a causality: one variable causes something in the other variable
Also called ‘experimental research’
We use stronger verbs for causations: causes, increases, decreases, leads to, changes
The four big validities
- Construct validity
- External validity
- Statistical validity
- Internal validity
→ Depending on the type of claim being tested, some types are more/less important
Construct validity
How well the variables in a study are measured or manipulated
The extent to which the operational variables in a study are a good approximation of the conceptual variables: do we have evidence that we are measuring what we want to measure?
External validity
The extent to which the results of a study generalize to some larger population
We measure something in the lab and look at the possible generalization and to what extent we think we’ll find a similar situation in real life
Statistical validity
How well the numbers support the claim: how strong the effect is and the precision of the estimate
Also takes into account whether the study has been replicated: if we state that there is a relationship between two variables, do we really see this relationship in the numbers and data
Internal validity
In a relationship where one variable (A) and another (B), the extent to which A, rather than some other variable (C) is responsible for changes in B
Four types of validity and frequency claims
Construct: how well has the researcher measured the variable in question?
Statistical: we get an estimate, but what is the confidence interval of the estimate? are there other estimates of the same percentages?
Internal: not relevant because frequency claims are not about causality
External: to what populations, settings and times can we generalize this estimate? how representative is the sample? was it a random sample?
Four types of validity and association claims
Construct: how well has the researched measured each of the variables? reliable?
Statistical: what is the estimated effect size? how precise is the estimate? what do estimates from other studies say?
Internal: not relevant because association claims are not about validity (! no causal claims based on associations)
External: to what populations, settings and times can we generalize this estimate? how representative is the sample? how did we draw it from the population?
Four types of validity and causal claims
Construct: how well has the researcher measured or manipulated the variables?
Statistical: what’s the estimated effect size? how precise is the estimate? what do estimates from other studies say?
Internal: was the study an experiment? does the study achieve temporal precedence? does the study control for alternative explanations by randomly assigning participants? does the study avoid internal validity threats?
External: to what populations, settings and times can we generalize this estimate? how representative is the sample? how representative are the manipulations and measures?
Three criteria you need to meet to be able to say there is a causal relationship
- Covariance: show that there is a relationship between the variables (before saying it’s a causal one)
- Temporal precedence: cause needs to come first in time and the effect needs to come afterwards and so further in time
- No alternative explanations: differences between groups are only due to differences in independent variable
Spurious associations
Some variables may correlate, even though there is no causal relationship whatsoesver
We are often tempted to believe that correlations are a sign of causality
Four causal models that can explain positive correlations (that are not causations)
- Directionality problem: you don’t know whether variable A influences variable B, or the other way around
- Feedback relations: the effect can go in both directions, variable A improves variable B and variable B improves variable A
- Confouding: a third variable C that explains the relationship between variables A and B
- Selection bias: there is a relationship because of variable C
The Belmont report: three principles to use in experiments
- Respect for persons: informed consent, protect vulnerable groups
- Beneficence: look at the balance between risks and benefits for participants/society
- Justice: fair balance between people participating in study and people benefitting from study
APA guidelines: five general principles that apply to psychologists
- Beneficence and nonmalifience
- Fidelity and responsibility
- Integrity
- Justice
- Respect for people’s rights and dignity
Informed consent
Form/document describing procedures, risks and benefits of research
Also describes how data will be treated
Problem: more and more information is required to be in the form, so participants do not always read it
Deception
Researchers sometimes withhold information from participants
Deception through omission: not disclosing all information
Deception through commission: lying
Sometimes necessary to avoid reactivity in participant
Participants may experience negative emotions when they learn about deception → may harm trust in scientific research
Debrief is necessary
Debriefing
Required for studies that use deception
Often required for any study done in an academic context
Purpose: reestablish trust, give information about study, opportunity for participants to learn something from study