文档介绍：Experimental Study
主讲:孙媛
1
is an experimental method?
Experiments were first used in the natural sciences. All of us have had the experience of undertaking either a physical or chemical experiment in a laboratory. What have left in your memory by these experiments are tubes, chemicals, wires and other materials. What is an experiment in a social science? I will answer this question first by a conceptual definition.
2
The experimental method is a scientific method that changes gradually conditions in plan under a certain control, and according to observation records and research data, determines the causality between conditions and the phenomenon by measuring the panying phenomena and changes, then finds and summaries the objective laws of Second Language Acquisition.
3
basic premise of an experiment
The basic premise of an experiment is that all factors save one are held constant.
The single factor is varied to see what effect it has on the phenomenon under investigation.
As stated earlier, experiments have two criteria: ① there are at least two groups included in the study, a control group and an experimental group; ② the subjects are randomly assigned to one of those groups.
4
do we have two groups?
The purpose of having the two groups in the study is that if one group is treated in one manner, and another in a different manner an