Data Collection Sheet
2 Comments, 1 Answer
The Disadvantages:- If you forget something you cannot usally go back especially if the data collection is anonymous You will never recieve 100 % back There is a danger of questionnaire fatigue Respondents may misunderstand questions Those who have an interest in the subject may be more likely to respond skewing the sample.
Hope this helps.
Some advantages of questionnaires: The responses are gathered in a standardised way, so questionnaires are more objective, certainly more so than interviews. Generally it is relatively quick to collect information using a questionnaire. However in some situations they can take a long time not only to design but also to apply and analyse (see disadvantages for more information). Potentially information can be collected from a large portion of a group. This potential is not often realised, as returns from questionnaires are usually low. However return rates can be dramatically improved if the questionnaire is delivered and responded to in class time. Hope this helps, Dave :)
Census (every member of population are asked) AD - Accuracy DIS - Time and Cost
Sampling AD - Speed and Cost DIS - Loss of Accuracy
Modelling (involves either Normal Distribution or uniform Distribution) AD - Cost and Way of predicting DIS - Loss of Accuracy
Median AD - Excludes extreme values DIS - Does not inclue all data
Mean AD - Includes all data, Used in tests DIS - Includes outliers
IQR AD - Only looks at middle 50% of results