In the article "IQ Scores are Up and Psychologists Wonder Why", New York Times reporter Trish Hall noted that people are now scoring substantially higher on IQ tests than they did in the past. "Studies show that if children took the same (1932 IQ) test today, half would score above 120 on the 1932 scale," writes Hall. Currently, IQ scores have a mean of 100, a standard deviation of 15 and a normal distribution.

According to the above article, if today's American children took the 1932 IQ test, the mean score would be 120 instead of 100 as it was in 1932. Identify at least one factor that might partially explain the rise in IQ scores.