Chapter 12

Chapter 12

1. Types of Bias

   • Nonresponse bias - sampled individuals won't or can't respond.
   • Response bias - answers may be affected by external influences
   • Voluntary response
   • Convenience
   • Undercoverage - certain individuals are selected less

2. Population

   • Sample - a subset of a population examined to learn about the population
     • Types of Samples
       • Simple random sample - every individual has an equal chance of being selected
       • Stratified samples - identify sub groups and sample within each
       • Cluster sample - randomly select among heterogenous subgroups that each resemble the population
       • Systematic samples - can work sometimes and are often the least expensive
       • Multistage - All of the above
     • Sampling Frame - individuals from whom the sample is drawn
     • Sampling variability - tendency of randomly drawn samples to differ
   • Population Parameter - number value for population we hope to be true