Question: Every 10 years, the United States takes a census. The census tries to count every resident. There are two forms, known as the "short form," answered by most people, and the "long form," slogged through by about one in six or seven households chosen at random. According to the Census Bureau (www.census.gov),". each estimate based on the long form responses has an associated confidence interval."
Why must the Census Bureau base these confidence intervals on t-models? The Census Bureau goes on to say, "These confidence intervals are wider. for geographic areas with smaller populations and for characteristics that occur less frequently in the area being examined (such as the proportion of people in poverty in a middle-income neighborhood)."