W1 Chapter 2.2 - Establishing Relationships among Variables Flashcards
What is the definition of a variable?
A dimension along which two or more variations exist
What are the two reasons why it is important to go beyond case studies?
- Generalisability
- The need to examine a range of variability
What are the two kinds of relationships between variables?
- Correlation
- Causality
What are the two aspects of a correlation relationship?
- Direction
- Strength
How is correlation “strength” defined?
Strength is the degree of accuracy with which you can predict values on one dimension from the values on the other
How is the strength of a correlation represented?
By a number called the correlation coefficient (r)
What r value (correlation coefficient) is used for strong correlations?
0.6 to 0.8
What r value (correlation coefficient) is used for moderately strong correlations?
0.3 to 0.5
What r value (correlation coefficient) is used for weak correlations?
Below 0.3
What is the definition of statistical significance?
The likelihood of an effect occurring by chance alone
What is the definition of clinical (practical) significance?
When an association is large enough to have some practical importance
What is the definition of causality?
A relationship such that variation in one dimension produces variation in another
What is the definition of the third variable problem?
The possibility that an unmeasured variable caused variations in both of two correlated variables
What is the definition of the experimental method?
The method in which one variable is manipulated to test for causal influence on another variable
What are the two defining characteristics of experimental research?
- One variable is manipulated
2.
What is the manipulated variable called?
The independent variable
What is the definition of the independent variable?
The variable manipulated in an experiment and tested as the cause in a cause-effect relationship
What is the definition of experimental control?
The holding constant of variables that are not being manipulated
What is the definition of random assignment?
The process of putting people randomly into groups of an experiment so that their characteristics balance put across groups
What is the definition of a dependent variable?
The variable measured as the outcome of an experiment; the effect in a cause-effect relationship
What is a good rule of thumb for determining that a study is correlational?
any time when groups represent “naturally occurring differences” or are formed on the basis of some “characteristic that you measure”
What are the two drawbacks of experimental research?
- It is sometimes unclear which aspect of the manipulation was important
- Experiments usually occur over a short timeframe
What does Underwood, 1975 believe is the only way to really understand personality?
To look at naturally occurring differences between people
What is the definition of a multi factor study?
A study with two (or more) predictor variables
