Concept explainers
(a)
To Explain: that it would be unfair to pay the teachers of all 120 schools more for their good attendance than to equate the number of teachers attending this year with the previous year.
(a)
Answer to Problem 64E
Not control group
Explanation of Solution
It is not a safe idea to equate this year to last year because lurking variables might have evolved over time. A lurking variable can be omitted from the study as its presence is unclear and has a significant impact but is not included in the predictor variables under consideration.
(b)
To write: a couple of phrases about how this experiment will be structured.
(b)
Answer to Problem 64E
60 arbitrary chosen schools would receive the offer, where the other schools will not receive the offer.
Explanation of Solution
They got the authorization to take pictures of the teacher and the classroom at the beginning and at the end of the day at 120 rural schools for observation, and to pay the educator extra for good attendance, tested with the photographs, so the impact of attendance could be studied. The 120 rural schools are arbitrarily split into two classes of about 60. In one group, give higher pay for teachers' participation, do little with the other group. Compare teachers' attendance at the end of the study period.
Chapter 4 Solutions
The Practice of Statistics for AP - 4th Edition
Additional Math Textbook Solutions
Algebra and Trigonometry (6th Edition)
Thinking Mathematically (6th Edition)
College Algebra (7th Edition)
Elementary Statistics: Picturing the World (7th Edition)
A First Course in Probability (10th Edition)
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