在經濟系一年級的數學課中，set是其中一個比較難解釋有何用處的課題，因為本科經濟學課程基本上用不著。我為今年的第一份功課思前想後，最後嘗試用一個統計陷阱來作為例子。
It is not easy to explain what is the use of sets to first-year economics majors since it is rarely used in the undergraduate economics curriculum. I ended up using a statistical paradox in the first assignment.