SOLUTION: One hundred teachers attended a seminar on mathematical problem solving. The attitudes of a representative sample of 12 of the teachers were measured before and after the seminar.
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Question 1142201: One hundred teachers attended a seminar on mathematical problem solving. The attitudes of a representative sample of 12 of the teachers were measured before and after the seminar. A positive number for change in attitude indicates that a teacher's attitude toward math became more positive. The 12 change scores are as follows:
3; 8; - 1; 2; 0; 5; - 3; 1; - 1; 6; 5; - 2
What is the mean change score?
What is the standard deviation for this sample?
What is the median change score?
Find the change score that is 2.2 standard deviations below the mean.
You can put this solution on YOUR website! mean is 1.917
sd is 3.502
median is middle of ordered numbers -3/-2/-1/-1/0/1/2/3/5/5/6/8, here between the 6th and the 7th since with even number sample, there is not a unique middle. This would be 1.5
2.2 sd s below the mean is 1.92-2.2(3.5)=1.92-7.70 or -5.78
