Final answer:
The four types of quantitative research, ordered from least control to most controlled, are: descriptive, correlational, experimental, and causal-comparative.
Step-by-step explanation:
The four types of quantitative research, ordered from least control to most controlled, are:
- Descriptive research
- Correlational research
- Experimental research
- Causal-comparative research
Descriptive research involves observing and recording data without manipulating variables. Correlational research examines the relationship between variables. Experimental research involves manipulating variables and measuring their effects. Causal-comparative research compares groups that already have different levels of the independent variable.