1) Explain why length of a questionnaire determines its response rate.
What should be the length of the questionnaire has been debated for a long. There is a belief that if it is lengthy the respondents may not fill it and leave it incomplete. Therefore, resulting in low response rate. If the questionnaire has less number of questions there is a possibility of getting high response rate.

2) Why is covering letter necessary in a mailed questionnaire?
Covering letter explains the objective of the survey and it requests the respondents Questionnaire Method to fill it. The researcher through this letter assures the respondents the confidentiality of their answers and the usage of data for research purpose only.

3) Differentiate between open ended and close-ended questions.
Open ended questions are those questions where respondent give answer in their own language. They freely express their views and answer according to their interpretation. These questions are also called unstructured questions. Close-ended questions are structured questions. Every question has a number of alternate answers. A respondent has to select one answer. These questions are also called
precoded questions.

4) What is a rating scale?
Rating scale is a measuring tool that requires the observer to assign the rated object to categories or continuum that have numerals assigned to them.

5) Why pretesting is required before finalisation of questionnaire?
Pretesting as the name suggests is a process of finalizing the questionnaire before putting it to actual use. It is essential as it alerts the researcher to the weaknesses, trouble points, and ambiguity in the questions. After pretesting the researcher revises it and circulate to the target population.

6) State the advantages of web-based questionnaire
Web-based questionnaire has advantages over printed questionnaire. The former can be distributed and received back from the wide spread population automatically. The answers can be validated. It is easy, quick and inexpensive.

Keywords

Questionnaire : It is data gathering instrument in survey research. It is a list of written questions, which are to answered by the target population.
Open Ended Questions : They are also called unstructured questions. In such questions respondents express their views freely.
Close Ended Questions : They are also known as structured questions. These questions are having number of answers. The responded is asked to choose one from the given options.
Pretesting : Before finalizing the questions in the questionnaire it is circulated to a sample for their opinion and suggestions. It is also called pilot survey.
Response Rate : The number of respondents returned the filled in questionnaire.
Rank Order Scale : Respondents are asked to rank all items according to some specified order.
Scaling Technique : A finite sample of concepts or items is ordered along a continuum. This may or may not accompanied by qualitative measurement of the variable represented by continuum.
Weighted Index : Weighted index derives by multiplying the percentage of respondents (weights) with the numerical value assign to the scale, and dividing the product by total value of the scale in terms of percentage.

Source:IGNOU Study Material