Experimental Research Strategy. Chapter 7. Goal. The purpose of the experimental research strategy is to establish the existence of a cause- and- effect relationship between two variables. How.
The purpose of the experimental research strategy is to establish the existence of a cause- and- effect relationship between two variables.
To accomplish this goal, an experiment manipulates one variable while a second variable is measured and other variables are controlled.
In an experiment, a treatment condition (independent variables) is a situation or environment characterized by one specific value of the manipulated variable.
2 teaching methods, 3 levels of lighting
The different values of the independent variable selected to create and define the treatment conditions are called the levels of the independent variable.
(Traditional, Constructivist) (high light, Med light, low light)
The dependent variable is the variable that is observed for changes to assess the effects of manipulating the independent variable.
Student score in math , size of plants
All variables in the study other than the independent and dependent variables are called extraneous variables.
IQ, Temperature, Fatigue, Age, noise, oxygen,….
Just because an experiment takes place in an unnatural environment does not necessarily imply that the results are unnatural.
Example, studying gravity in vacuum
feather , hammer
Although it is relatively easy to demonstrate that one variable is related to another, it is much more difficult to establish the underlying cause of the relationship.
Number of smiles & life span
Eating fish & life span
Heavy lunch & life span
We need manipulation
Difference between Engineer and Education (PE , non-PE) students in their reading speed.
They think they are getting a medicine
Research studies conducted in a real- world environment are called field studies,
In these studies, the researchers create an emergency situation, then manipulate
variables within the emergency and observe bystander responses.