As you identify your data sources each must be evaluated. Evaluation consists of three steps. Data must be tested for validity and reliability and your must review its practicality. Validity means that the data provides objective, accurate information about the research topic. Reliability is a measurement concept that refers to the consistency of results obtained with a measuring device.
Practicality refers to the cost, the time, and the convenience of using a data source.
There is a lot of data out there, especially on the WWW, but can your afford to use it. Return to the problem you identified earlier in this lesson. Jot down the data sources you considered and put the tests of validity, reliability and practicality to them.