The Curious Statistician

 

at least when compared to the discount between $98 and $99.  Research confirms this.  One study found that used cars drop disproportionately in value when they hit 10,000 mile markers.

In the achievement realm, however, humans strive for the round number.  One study found a gap in SAT college prep test scores just below certain round numbers, such as 1300.  The reason?  Students are more likely to retake the SAT if they fall just below these benchmarks, in hopes of reaching a "round number."  Some will improve, moving them above the benchmark, and creating a relative "shortage" just below the benchmark.  (If students take the test and improve, many will choose to report only the better score.)

Another intriguing study found that baseball players are 4 times more likely to end a season with a batting average of .300 than .299.   Batters have multiple strategy options at the plate, and, at the very end of the season, a batter hitting just below .300 may choose to avoid strategies with lower probabilities of getting a hit, such as hitting for power (seeking fewer but bigger hits), or not swinging at close pitches (increasing the probability of a walk, which leaves the average unchanged).

For more details, see http://www.psychologicalscience.org/index.php/news/releases/students-are-more-likely-to-retake-the-sat-if-their-score-ends-with-90.html