4 ms·

After someone turns 30 (according to AAA [0]) their likelihood of entering an accident decreases until they reach ~70 years old. [0] https://aaafoundation.org/

• thatcat 5y ago
  The variance overlaps from age 20-59 so you can't statistically differentiate anything conclusive about the difference between those groups. An alternative conclusion is that retired people (65+) don't drive as much and are able to avoid rush hour / high risk times to drive. https://www.fhwa.dot.gov/ohim/onh00/bar8.htm https://www.fhwa.dot.gov/ohim/onh00/bar8.htm
  • iaw 5y ago
    Variance overlapping isn't a reason to discount this analysis. Also note that the variance narrows substantially for older age groups. So effectively what the variance says is that some younger people are vastly more responsible drivers than other young people but older people tend to be more responsible in general.
    • thatcat 5y ago
      There could be a number of factors that have nothing to do with responsibility, that's a narrative that gets added to explain the data. You need to do ANOVA test to verify any significant difference in data sets, not look at avg - esp when its not a controlled experiment.