Research Methods Flashcards
the belmond report 3 principles
- respect: informed consent, special groups protection
- justice: right balance between the people that benefit from the research and the people that participate in it
- beneficience: participants should be protected from harm and ensured well being. ook confidentiality hoort hierbij.
APA 5 general principles
- respect
- beneficience
- justice
- fidelity and responsibility (trust, professional)
- integrity (accurate info, honest)
deception through omission
witholding info
deception through comission
lying
difference data fabrication and data falsification
- Data fabrication: Inventing data to fit the hypothesis
- Data falsification: Influencing a study’s results
3Rs from animal research
replacement (liever een andere methode), refinement (minste distress), reduction (zo min als mogelijk dieren)
interaction effects
when the original independent variable depends on the level of another independent variable
spreading interaction
an interaction between two independent variables “only occurs when..”
moderator
independent variable that changes the relationship between the independent and dependent variable
factorial design 2 effects
main and interaction effects
interaction effects wanneer ?
als de lijnen parallel zijn: GEEN interactie effect. anders wel.
factorial variations
- Independent-groups factorial designs: Both independent variables are studies as independent groups (E.g.: in a 2×2 factorial design, there are four different groups of participants in the experiment)
- Within-groups factorial designs: Both independent variables are manipulated as within-groups (E.g.: in a 2×2 factorial design, there is only one group of participants, but they participate in all four combinations of the design)
- Mixed factorial designs: One independent variable is manipulated as independent-groups, and the other is manipulated as within-groups
three way design
- Results in three possible main effects
- Results in three possible two-way interactions
three way interaction
Three-way-interactions: A two-way interaction that depends on the level of the third independent variable
obscuring factor
hierdoor kan je geen relatie zien tussen independent and dependent variable
internal validity
zijn er andere factoren die een rol spelen?
design confound
andere explanation omdat het studie design gewoon niet goed is
selection effects
the participant groups are systematically different
order effects
the order in which the interventions are presented lead to differences: participants get tired etc.
maturation threat
spontaneous remission (behaviour just changes)
history threat
a factor unrelated to the study influences the outcome for the whole group (COVID)
regression to the mean
when a group has an extreme value as mean, it is most definitely going to be less the next time.
attrition threat
drop out
testing threat
participants scores change when they take a test multiple times
instrumentation threat
the instrument changes -> measures differently
observer bias
researchers expectation have influence
demand characteristics
participant knows what the study is about
null effect
gewoon geen effect
between group obscuring factors
- weak manipulation -> door slechte study design geen goede manipulatie (manipulation check!)
- insensitive measures (door slechte measures kan je geen verschil meten tussen de groepen)
(- ceiling effect: all scores clustered at the end, te makkelijk) - floor effect: all scores clustered at the bottom, te moeilijk)
dus obscuring factors van verschillen zijn …
within group issues. de grafieken liggen dan verder uit elkaar.
within group issues of obscuring factors
- Noise: Unsystematic variability
- Measurement error: A human or instrument factor that can inflate or deflate a person’s true score on the dependent variable
- Individual differences (use within group design to solve this, or more participants)
- Situational noise: External distractions (control wat je kan controleren, anders randomiseren)
strengths of within groups
control for individual differences
fewer participants needed
strength of between group design with more than one independent variable
- two for the price of one
- you can study interaction effects
maar (-) wel 2x zoveel participanten nodig.
hoe kan je zien of er een 3 way interactie is
als de twee grafieken hetzelfde zijn voor verschillende locaties bijvoorbeeld -> dan geen interactie effect. als ze ander zijn is er wel een interactieeffect.
participant variables
variables that you do not manipulate. these are also called additional independent variables.
mixed factorial design
manipulate one independent variable between subjects and another within subjects.
For example, a researcher might choose to treat cell phone use as a within-subjects factor by testing the same participants both while using a cell phone and while not using a cell phone (while counterbalancing the order of these two conditions). But he or she might choose to treat time of day as a between-subjects factor by testing each participant either during the day or during the night (perhaps because this only requires them to come in for testing once). Thus each participant in this mixed design would be tested in two of the four conditions.
within-group design
pretest -> intervention -> posttest. in the same group
voorbeeld van regression to the mean
mensen die zich depressief voelen zullen zich de volgende keer waarschijnlijk minder depressief voelen, aangezien ze zich aanmelden voor therapie op hun laagste punt. daardoor wss beter de next measurement.
mixed factorial design
pretest -> intervention -> posttest
pretest ———————–> posttest
non-specific effects
effects not due to the treatment, but due to the expectation of being treated (bijvoorbeeld meer gaan sporten door motivatie therapie)
wat is een oplossing voor non-specific effects
mixed factorial design with control group on a waitlist
differences non-specific effects and placebo effect
non-specific: differences because you think you will be treated
placebo: because you are being treated
hoe doen ze vaak control condition bij psychological interventions
positive control group: kijken of de interventie beter is dan de traditionele interventie.
difference observer effect and observer bias
Observer bias: The researcher may see differences between the conditions that are not actually there
Observer effect: The researcher may treat participants differently depending on the condition they’re in