MATH 110 Chapter Notes - Chapter 2: United States Census Bureau, Quartile
Document Summary
The mean and the median provide two different measures of the center of a distribution. But a measure of center alone can be misleading. The us census bureau reports the median income in 2012 was ,017. The mean was much higher ,274 because the distribution of incomes is so skewed to the right. But the (cid:373)ea(cid:374) a(cid:374)d (cid:373)edia(cid:374) do(cid:374)"t tell the whole story: The bottom 20% had incomes less than 20,593. Households in the top 5% took in more than ,156. We are interested in the variability of incomes as well as their center. The simplest useful numerical description of a distribution requires both a measure of center and measure of variability. Arrange the observations in increasing order and locate the median in the ordered list of observation. The first quartile, q1, is the median of the observation whose positon in the ordered list is to the left of the location of the overall median.
