Physical a students. Let\'s look at the data for physical activity and consumpti
ID: 3312599 • Letter: P
Question
Physical a students. Let's look at the data for physical activity and consumption of fruits. We categorize physical activity as low, moderate, or vigorous and activity generalily declines when students leave high school and enroll in collego. This suggests that college is an ideal setting to promote physical activity a sampla of 1102 college fruit consumption as low, medium, or high. Hare s the two-way tabie that summarizes the data. Physical acti Fruit consumption LowModerate Vigorous 69 207 125 110 442 293 170 169 632 569 320 Medium High Total 25 1182 test la to caleulate the expected cell counts. Let's start with the cell for students with low fruit consumption and loue physical activity. Use the following formuls for expected cell counts Using the formula, we need three quantities: (1) the corresponding rov, tots!, 69·the numberet students who have law fruit consumption (2) the column total, (2) the total number of students, 62 ··thQ number ef students who have tov, physical activity, and The expected cell count is therefare the folowing 559) Note that although any observed count of the oumbar of students must be a whole mumber, an sxpected count need not be Calculations for the other·ght eali, in the× table nre perform.d in the same way, with these nine opeted courtna sre now ready te us formuts for the The first term in the sum comes from the cell inr students with low fruit congumption and lovs physical activity, The obrervedExplanation / Answer
2) The column total, 108, the number of students who have low physical activity
The expected cell count is therefore the following
108*569/1182 = 51.99
the first term in the sum comes from the cell for students with low fruit consumption and low physical activity. The observed count is 69 and the expected count is 51.99
(69 - 51.99)^2/51.99 = 5.57
chi-square = 14.06
df = (3 - 1) (3 - 1) = 4
Observed Low Moderate Vigorous total Low 69 207 293 569 Medium 25 125 170 320 High 14 110 169 293 Total 108 442 632 1182 Expected Asian American White African Against Tax 51.990 212.773 304.237 In Favor 29.239 119.662 171.100 No opinion 26.772 109.565 156.663