Last year, the average math SAT score for students at one school was 475. The headmaster introduced new teaching methods hoping
to improve scores. This year, the mean math SAT score for a sample of students was 481. If the teaching method had no effect, there would be roughly a 3 in 10 chance of seeing such an increase. Does the result have practical significance? Why or why not?
If the method was ineffective, the chance of an increase this large was 3/10, or 30%. This means with an ineffective teaching method, there was a 100-30 = 70% chance of not seeing a score increase this large.
Since we did see a result this large, and 30% is not a very large chance, we can say that the method was most likely effective.
I would argue that it does due to that if it increased, it's either from a 30% chance that nothing changed or that the teachers did it. Since 100-30=70, there's a 70 percent chance that the teaching effect did work!
