Experimental Design Flashcards
Requirements for making a causal claim: a cause and effect relationship requires 3 elements = Temporal Precedence, Covariation between the two variables, and eliminating plausible alternative ___
explanations.
Internal Validity: the degree to which ___ in the dependent variable can be attributed to the independent variable, rather than to another variable. (ex - confounding variables)
changes
IV——-> DV
Confounding Variables= are there any ___ explanations
alternative
Experiments= experimental designs are intended to investigate __ relationships
causal
experiments involve the 1.___ of an independent variable (IV)
Participants are then 2.___ assigned to different levels(conditions) of the (IV)
The researcher then measures the dependent variable (DV) and 3. ___ the different levels of the IV to see if they differ on the DV
manipulation, randomly, compares
- Independent variables manipulation - Independent variable (IV): is what the researcher directly __ to determine its influence on peoples behavior the (the DV).
In an experiment the researcher attempts to manipulate the IV while keeping all other variables ___
By doing this, the researcher can be confident that any changes in the DV are the result of the manipulation and __ a confounding variable.
manipulates, constant, not
Levels of the independent variable (aka experimental conditions) : since the IV is a variable, there must be at least _ levels of the IV
levels are also known as ___
ex: level 1 - ppl study alone, level 2 - people study in a group.
ex 2: level 1 - people watch a scary movie, level 2 - people watch a funny movie, level 3 - people don’t watch a movie.
2, conditions
Dependent Variable= a response or behavior that is __, the researcher want to see if the levels of the IV produce different means on the DV
ex 1: the DV could be peoples test scores. ex 2: the dv could be participants anxiety level after the movie.
measured,
- Random Assignment = is when the researcher randomly places participants in different levels of the IV (this should not be systematic)
each participant has an __ change of being in ant of the experimental conditions (levels)
Random assignment equalizes the conditions in regards to individual differences.
creates an equal proportion of good test takers in both conditions.
equal
one way experimental design = has __ independent variable
There has to be at least 2 levels of the independent variable.
one
Independent groups design ( __ - subjects Design) - are experimental design in which participants are randomly to only __ experimental condition
between, one
one way independent (between - subjects design) - 2 levels of the independent level
level 1 : take the course
level 2: don’t take the course
Random __ to conditions.
participants have an equal chance of being assigned to either 1. take the course 2. not take the course
assignment
Repeated Measures Designs ( __ participants Design) - an experimental design where the same participants are assigned to __ level of the independent variable
within, each
Advantages of repeated measures design (within participants design) : advantages - __ any effects due to differences between people. - this makes it easier to obtain significant results.
require 1/2 the number of participants as a independent groups design. - good for when the pool of potential participants
eliminates
Disadvantages of repeated measures design (within participants design) - the main disadvantage is that being exposed to the IVs and DVs multiple times can __ participants responses to the DV ( order effects)
affects.
