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The grades of a class of 10 students on a midterm exam (x) a…

The grades of a class of 10 students on a midterm exam (x) and on the final exam (y) are as follows: Midterm (x) 77 50 71 72 81 94 96 99 67 83 Final (y) 82 66 78 34 47 85 99 99 68 98 A simple linear regression is fit to this data set to estimate the final exam grade (y) from the midterm exam grade (x). Estimate the final examination grade of a student who received a grade of 85 on the midterm.

An experiment is conducted to assess whether physical therap…

An experiment is conducted to assess whether physical therapy or yoga is useful at reducing patient falling in the hospital. 19 patients were included in the study. Patients were randomly assigned to one of three groups: (1) A 6 month physical therapy program, (2) A 6 month yoga program, or (3) No program. The number of times the patient fell was recorded over a two-year period after each program. The data is shown below (1) Physical Therapy (2) Yoga (3) No Program 2 1 7 1 0 8 4 2 5 6 3 9 4 3 4 2 1 2 7 A hypothesis test was conducted to assess whether there is a difference in the mean number of times patients fell in each group. What would be the treatment and error degrees of freedom used for the distribution of the test statistic? Treatment degrees of freedom: [treatmentdf] Error degrees of freedom: [errordf]  

A categorical variable is used in a multiple linear regressi…

A categorical variable is used in a multiple linear regression model. The levels are Red, Orange, Yellow, Green, Blue, Indigo, and Violet. How many indicator (binary) variables would be needed to represent this categorical variable in a multiple linear regression model?