Task 7 Flashcards
Causal relationship can be …-directional or …-directional
Undirectional
A→B but NOT B→A
- Flowers open, because the sun has risen
- The sun rises, not because flowers open
Bidirectional
A→B and B→A
1. There are fewer rabbits, because there are a lot of foxes.
2. There are fewer foxes, because there are fewer rabbits
What do you know about correlational relationships?
There is no causal link established (yet)
Change in one variable occur together with changes in a second variable
=the covary
What defines correlational research? Name 4 characteristics
- is non-experimental
- no variables are manipulated
- can determine: direction, magnitude and form of correlation
- Value of Predictor Variable predicts value of Criterion Variable
Explanier the Third-Variable Problem
Name an example
Two variables covary, because they are both influenced by the same third (hidden) variable
Example: There is a moderate correlation between sunscreen use and skin cancer. The amount of strong sunlight is the third variable.
Explanier the directional problem
Name an example
The challenge of determining with factor causes which
Example: Watching violence on TV might cause people to have violent tendencies. People with violent tendencies might be drawn to watch violence on TV
When do you use correlational research?
for fast identification of potential causal relationships
if variables are not manipulatable (e.g. ethical reason)
for research on naturally occurring phenomena (seasons, wether)
What are extraneous variables?
they are outside of the experimental design but still influence the dependent variable
can be controllable: calculator used at exam
can be uncontrollable: difference in skill
each study has thousands
Which use does a control / placebo group have?
is often included to determine if true effect exists
What does a random assignment do?
Solves problem of uncontrollable extraneous variables, because it balances differences out between groups
Name 6 criterion for causation
• Strong association • Consistent association • Independent V precedes outcome • Outcome increases with increase of Independent V • Causation is plausible (can also apply for quasi-experiments) -exclude alternative explanations
What are Quasi-Independent variables? What do they do?
- Natural groups (gender)
* Reduces error variance
What is demonstration?
• Only one treatment condition
• Can demonstrate how something plays
out under certain conditions. →Both cannot establish causality
When do you use developmental design?
• to establish relationship between change in behavior and chronological age
• Age cannot be randomly assigned
• Therefore, design is considered to be
correlational or as having a quasi- independent variable
What are you doing by using cross-sectional design?
• Measuring different age groups on a specific outcome variable
• Allows for efficient data collection
• Generation effects: age groups might
be influenced by events of their time
What is a longitudinal Design?
here you following a group of people over time
clearly shows developmental changes
What are the problems of a longitudinal design?
• Cross-generational effects: results might not apply to a different generation • Subject mortality (if nonrandom) • Carry over effects • History
What is an extraneous variable?
- Any variable outside of the experimental set up that EITHER influences the Independent or Dependent variable
- So any variable that could influence the experiment but is not included can be considered extraneous (Lurking, Confounder, Mediator, Moderator)
What is a confounder?
Any variable that influences BOTH the Independent and Dependent variable of your experiment
Reason why correlational research cannot establish causation (there could always be a unknown confounder)
What is the moderator?
remember the term sub groups
• A third-variable that influences the relationship between two variables
• Can be the source of interactions (but not for everyone)
There is a relationship between stress (IV) and dpression (DV) But this relationship lack for people with a strong support system (moderator)
What is a mediator?
remember the term via
• Mediator: a third variable that explains the indirect relationship of the independent and dependent variable
• (“man in the middle” via=durch)
if the relationship between independent variable and mediator and the relationship between mediator and dependent variable exists; the relationship between independent and dependent variable can be become meaningless
What is meant by common response (think about third variable problem)
Wut is a lurking variable?
A correlation of two variables can be because of causal relationship or a lurking variable (Third- Variable).
The lurking variable can be the actual reason for changes in the explanatory and dependent variable and there is no actual relationship between explanatory and dependent (Common response)
Example: There is an association, but no causal relationship between use of sunscreen and skin cancer. Both factors are influenced by amount of strong sunlight.
What is a confounder?
The lurking variable can also be a confounder. Both the explanatory and dependent variable do have a connection, but they are both influenced by a third variable
when do extraneous variables become confound?
Extraneous variables only become confound if it systematically varies with the two variables that are studied
What is the conceptual confound?
occurs if cause and consequence overlap
you can not conclude that A leads to B, if A and B are partly the same
What is the difference of a experimental and a quasi experimental design?
The difference is that participants ate NOT randomly assigned to conditions
comparing smokers versus non-smokers
