CRM 204 Lecture Notes - Lecture 6: Non-Sampling Error, Cover Letter, Sampling Error
Document Summary
Crm 204 criminal justice research and statistics (october 17th, 2012) Difference between a sample and a population from which it is selected. Difference between the sample and population caused by deficiencies in sampling such as inadequate sampling frame or non-response or poorly designed measures or from flawed data processing. A source of non-sampling error that occurs whenever some members of the sample refuse to co-operate, cannot be contacted or cannot supply the data required. Development of scales and indexes to measure quantitative data in a systematic way. Avoid asking questions beyond the person"s capability. Reframe potentially threatening questions (social desirability can cause overreporting or underreporting) Choose wisely between open and closed questions. Consider question order or sequence of questions. Consider trade-off between gathering lots of data and gathering less data but accurate (and complete) data. Electronic surveys and web surveys (refer class hand-out on online surveys) Send a replacement questionnaire (3-4 weeks later)