11.1 Paired marbles t-test

The marbles were pre-split on 5.1 grams and 5.2 grams.

Less massive on one side, more massive on the other. 


This term the students detected a mass difference with the results being statistically significant. The students are always surprised when they get the mass difference correct. One only has a sensation of a faint difference, but no surety. 

Yet 14 of 18 were correct with one tie and three incorrect, far from the 9|9 split that might be randomly expected.


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