One hundred teachers attended a seminar on mathematical problem solving. The attitudes of 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 twelve change scores are as follows. 3; 7; - 1; 1; 0; 5; - 3; 2; - 1; 6; 5; - 2

Question

Gustavo Estes

Mathematics

7 September, 19:39

One hundred teachers attended a seminar on mathematical problem solving. The attitudes of 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 twelve change scores are as follows. 3; 7; - 1; 1; 0; 5; - 3; 2; - 1; 6; 5; - 2

+3

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Michael Barber · Answer 1

3

Step-by-step explanation:

Mean = (3+7+-1+1+0+5+-3+2+-1+6+5+-2) / 12

= 1.833

median is middle of ordered numbers - 3/-2/-1/-1/0/1/2/3/5/5/6/8/7 here between the 6th and the 7th since with even number sample, there is not a unique middle. This would be 1.5

Standard deviation = √ 123.67/12

√10.3

=3.21

the change score that is 2.2 standard deviations below the mean.

1.83 - 2.2 (3.21)

= 5.232