Another benefit is that you can ask them a lot of questions and you can also get open answers from them, plus you can ask them what they want from you so you can meet their demands. 6. One problem of using postal questionnaire is that the body language of the person cannot be observed as the person cannot be seen.
Another problem with postal questionnaire is that people who do mail back the questionnaire might not have all of the questions answered in it. 7. Random sample means a group of people in which each member of the target population has an equal chance of being chosen.
8. The main difference between the quota and stratified sampling is that in the stratified sampling the researcher cannot select the individuals to be included in the sample, he doesn't have control over who will be in the sample, but in the quota sampling the researcher has control over who will be in the sample, he can contact certain people and include them in the sample.
9. One way that a sample can bias is that when the person is conducting