bg statistical package for social sciences spss 2 1447

2.1 Reasons Follow up data can not be sent immediately to the processing and analysis because of the many errors: • The quality of the interview: Interviewer misunderstood questionnaire,

Chapter 2

Data Cleaning

2.1 Reasons

Follow up data can not be sent immediately to the processing and analysis because of the many errors:

• The quality of the interview: Interviewer

misunderstood questionnaire, interviewers collected incorrect information, write to the wrong

questionnaire

• Input: false, shortcomings, redundant

2.2 Measures to prevent

• Design a questionnaire clear, easy to understand, easy to answer

• Selection and training of interviewers carefully

Interview a few tests before the interview so to avoid errors

• The questionnaire after the interview must be read check error control, edit before entering

2.3 Methods of Data Cleaning

• Use a frequency table

• Use a table combination of two or three

variables

• Use the Data-> Select case to filter out the

case of an error

• Combined with a program excel