sampling and its implications

the total category of subjects that is the focus of attention in a particular research project is known as the population

introduction

determinants of sample size

the required level of precision in the results

the level of detail in the proposed analysis

the available budget

opinion polls and sample size

confidence intervals

level of detail of analysis

budget

reporting size of sampling errors

small populations

introduction

random sampling in household surveys

multi-stage sampling

random sampling in site/visitor/intercept surveys

quota sampling

when one interview is complete. check through the questionnaire for comleteness and legibility

when you are ready with a new questionnaire stop the next person to enter the gate or entrance

stick strictly to this rule and do not select interviewees on any other basis

random sampling and mail surveys

the inital list of people to whom the questionnaire is sent in a postal survey may be the whole population or a sample