Examples of Type of Errors in Survey Research

1) Sampling Error• Random Sampling ErrorEx. If you want to study the attitudes of engineering students regarding library services, it would not be enough to interview every 100th person who walked into the library. That technique would only measure the attitudes of engineering students who use the library, not those who do not. In addition, it would only measure the attitudes of engineering students who happened to use the library during the time you were collecting data. Therefore, the sample would not be very representative of engineering students in general. In order to be a truly representative sample, every student at engineering would have to have had an equal chance of being chosen to participate in the survey.

2) Systematic ErrorSample design Errors are the following:

• Frame ErrorEx. In conducting telephone interview, many households are not listed in a current telephone book because they do not want to be listed or are not listed accurately because they have recently changed their telephone number regarding research about electricity consumption during Christmas season.

• Population Specification ErrorEx. Error in the estimation of the amount of travel on 'employer’s business' by personal vehicle, employer’s business' travel is defined as travel on the business of the employer (e.g. trips to meetings, trips between worksites etc), but excludes travel between home and work (i.e. commuting).

• Selection ErrorEx. Door to door interviewers might decide to avoid houses that do not look neat and tidy because they think the inhabitants will not be agreeable to doing a survey. If people live in messy houses are systematically different from those who live in tidy houses, then the selection error will be introduced into the results of the survey.

3) Measurement Error

• Surrogate Information ErrorEx. Kodak film was so popular in 80's. Their marketing line was Kodak sells film, but they don't advertise film. They advertise memories. It failed miserably in the marketplace when they suffered bankruptcy in 2000's. People love taking pictures but because of the rapid changes of technology they didn't survive because the real question was never in the research which is, would they adapt those changes to stay in the market.

• Interviewer ErrorEx. An interviewer conducted a street survey method and tries to influence a respondent on answering the survey questionnaires in a way respondent would be tempted to give untrue answers especially when the interviewer was good looking and very convincing. Error occurs when deliberate cheating takes place.

• Measurement Instrument BiasEx. Interviewer made open-ended questionnaires regarding brands that Doctors usually prescribe to their patients. There is a bias on questionnaire because it makes recording responses difficult and prone to recording error since doctors he would ask might have different preferences depending on their client's diseases.

• Processing ErrorEx. In evaluating UPHSL professors before the semester ends, student might enter the wrong response to a particular professor which he hates the most but was supposed to be intended to his favorite professor. There was an error since the survey document to a computer was transferred incorrectly.

• Nonresponse BiasEx. The marketing department of an airline made mail survey to their passengers in every flight regarding their services and satisfaction. Few months later, it proudly announced that it had a huge sample of passenger's feedback. Therefore, it could only mean that potential respondent is reached out but cannot or will not participate at that time when airline posted that survey.

• Response BiasEx. The respondents may have a good idea of how many times they visited a supermarket in the past month. However, they may not used to buy in that particular supermarket rather in public market. Rather than answering "No idea" in response to a question regarding which supermarket they used to purchase goods, the respondents may simply guess.