Contact Methods

1. Personal Interviews
   Advantages
   1- High response rate
   2- Great flexibility (ability to adapt/explain questions)
   3- Can show or demonstrate items
   4- Fuller explanations can be given
   5- Very timely data
   Disadvantages
   1- Relatively expensive
   2- Possibility of interviewer bias
   3- Personal nature of questions (e.g., age or income)
   4- Respondents not relaxed (put on the spot)
   5- Time may not be convenient for respondents



2. Mail Surveys
   Advantages
   1-Relatively inexpensive
   2- No interviewer bias
   3- Consistent questions (for all respondents)
   4- Large number of respondents can be included
   5- Anonymity
   6-Respondents can choose the most convenient time to answer
   Disadvantages
   1- Low response rates (relative to other survey types)
   2- Junk mail syndrome
   3- Impersonal nature


3. Telephone Surveys
   Advantages
   1- More flexibility compared to mail surveys
   2- Quick and inexpensive
   3- High response rates
   Disadvantages
   1- More obtrusive than mail
   2- Greater difficulties in rapport building
   3- Long-distance calls are expensive


4. Pros and Cons of Online Research

Advantages
1- Inexpensive
2- Fast
3- Accuracy of data, even for sensitive questions
4- Versatility

Disadvantages
1- Small samples
2- Skewed samples
3- Technological problems
4- Inconsistencies

Sampling Plan

Sample – segment of the population selected to represent the population as a whole”. (Require three decision)
---Sampling unit: Who is to be surveyed?
---Sample size: How many people should be surveyed?
---Sampling procedure: How should the respondents be chosen?

Types of Samples

1----Probability Samples
Simple random
Stratified random
Cluster
2----Nonprobability Samples
Convenience
Judgment
Quota