The authors of the paper “Development of Nutritionally At-Risk Young Children is Predicted by Malaria, Anemia, and Stunting in Pemba, Zanzibar” (The Journal of Nutrition [2009]:763–772) studied factors that might be related to dietary deficiencies in children. Children were observed for a length of time and the time spent in various activities was recorded. One variable of interest was the length of time (in minutes) a child spent fussing.
The authors comment that the distribution of fussing times was skewed and that they used a square root transformation to create a distribution that was more approximately normal. Data consistent with summary quantities in the paper for 15 children are given in the accompanying table.
Normal scores for a samples size of 15 are also given.
- a. Construct a normal
probability plot for the fussing time data. (Hint: See Example 7.31.) - b. Does the plot from Part (a) look linear? Do you agree with the authors of the paper that the fussing time distribution is not normal?
- c. Transform the data by taking the square root of each data value. Construct a normal probability plot for the square root transformed data.
- d. How do the normal probability plots from Parts (a) and (c) compare?
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Introduction To Statistics And Data Analysis
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