Reference Notes for Management
There are several sampling methods that may be used with any of the types of frames described above, individually or in combination. They are influenced by many factors, including:
Moderating variables influence the relationship between independent and dependent variables by modifying the effect of the intervening variables. Moderator variables, unlike extraneous variables, are measured and considered. Studies in TESL and language acquisition often include moderator variables (when they’re not the main focus of the research) such as the sex of the subjects, their age, their culture, or their level of English proficiency.
The intervening variables are abstract processes not directly observable, but which link the independent and dependent variables. Language learning and teaching typically take place inside the subjects’ heads, including various processes of language acquisition that can’t be observed by the researcher. It is a hypothetical variable used to explain causal relationships between variables. Experimental variables cannot be observed (that’s why they are hypothetical).
The intervening variable is sometimes referred to as a mediating variable or intermediary variable. An intervening variable is usually considered a subtype of a mediating variable in statistics. These terms have been used interchangeably for a long time, however, and the lines between them are somewhat blurry. In research terminology the intervening variable can be described as
