Difference between the two examples

Difference between first and second example
First example

• In this, the researcher is using a survey method to carry out the study.
• Here researcher is selecting the sample on a random basis i.e. out of 1000 primary school teachers in mumbai she is selecting 300 teachers randomly.
• To find out the oipinion of primary school teachers researcher might be using questionnair as a tool.
• For this survey method she requires only one group.

Second example

• In this researcher is using experimental method to carry out the study.
• Here researcher is selecting the sample randomly using a different method i.e. She lists everyone’s names on chits, and draws one chit out of the lot and writes that name under a column named linear CAI and non-linear CAI alternately and puts that chit aside.
• Hence, two groups of sample are selected for the study.
• Different treatment i.e linear CAI package to one group and non-linear CAI package to another group is given to check the effectiveness of the packages.