What are the kinds of errors you would expect in a Held survey by census method?

The following kinds of errors are likely to occur in a field survey by census method :

(i) Errors of Measurement: Suppose each student in your class is asked to measure the length of the teacher’s table in the class room. Every student is provided a separate measuring tape. If we compare the measurement taken by thp students, we will find that the measurements are not identical. The differences in measurements may arise because some students measured upto the nearest of the unit, while others measured to be nearest of the tenth place of decimal. Rounding of errors will always be there.

(ii) Errors due to Mishandling of the Questionnaire : The enumerator, or the respondent may misunderstand, or misinterpret some questions of the questionnaire. Since the scale of operations is large in such survey, large team of enumerators has to be employed. All enumerators may not be equally efficient. Some careless ones may not take their job seriously, even after intensive training. There may also be lack of coordination in the team work.

(iii) Recording Mistakes : The enumerator may commit errors in recording data. For example, he may record 13 instead of 31, and so on. Sometimes the handwriting is so bad and unclear that the tabulator may misread the recorded answers, while transferring data to files or computer.

(iv) Errors of Non-response : These errors arise when the respondent refuses to fill up the questionnaire, or the respondent is not available even after repeated visits of the enumerator. The magnitude of the errors will, generally, be large, if questionnaires are mailed to the respondent and not carried to him personally by the enumerator. The respondent, in that case, may not care, or feel too lazy to return the questionnaire duly filled. In many cases the questionnaires may be lost in the mail.

(v) Arithmetical Errors : If some questions require a little of arithmetical calculations, there is a possibility of such errors. For example, if the question is what was the expenditure on food last month. The head of the household will have to add expenditures on rice, wheat, salt, sugar, milk etc. and also on fruits and vegetables. The errors may occurs in recollecting the items, their prices and adding.