1. Calculate the expected cell count for a cell that has a row total of 35 and a
ID: 3208927 • Letter: 1
Question
1. Calculate the expected cell count for a cell that has a row total of 35 and a column total of 74. The total number of observations is 273. Use two decimal places.
2. The degrees of freedom for a chi-square statistic in a table with 5 rows and 4 columns is -- ?
3. Faculty at Public University are concerned about student success in math courses. In particular, the faculty would like to find a method of teaching math that lowers the "DFW" rate, which is the proportion of students who earn a D, F or withdraw (W) from a math course. The faculty try three different methods of teaching the course, and record student grades. Here's what they find:
The column "A" shows how many students earned a grade of A, "B" is the number of students who earned a grade of B, etc. DFW is the number of students who earned either a D, F or withdrew from the course (dropped the course). Use this information to answer the following questions.
a) What percentage of students who were taught using Method 1 earned an A? Use one decimal place.
b) Of the students who earned an A, what percentage were taught using Method 1?
Method A B C DFW Method 1 45 67 32 18 Method 2 50 75 35 20 Method 3 32 86 41 34Explanation / Answer
1. Expected cell count = (Row Total x Column Total) / Grand Total = (35 * 74)/ 273 = 9.49
2. Degrees of freedom = (Row - 1)(Column - 1) = (5 - 1)(4 - 1) = 12
3. a) % of students who were taught using method 1 earned an A = 45/ (45 + 67 + 32 + 18) = 5/18 = 27.8%
b) % of students who earned an A, were taught by method 1 = 45/(45 + 50 + 32) = 45/127 = 35.4%
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.