Grades again In some situations where the expected cellcounts are too small, as in the case of the grades givenby Professors Alpha and Beta in Exercise 39, we cancomplete an analysis anyway. We can often proceed aftercombining cells in some way that makes sense and alsoproduces a table in which the conditions are satisfied.Here we create a new table displaying the same data, butcalling D’s and F’s “Below C”:a) Find the expected counts for each cell in this newtable, and explain why a chi-square procedure is nowappropriate.b) With this change in the table, what has happened tothe number of degrees of freedom?c) Test your hypothesis about the two professors, andstate an appropriate conclusion. Prof. Alpha Prof. BetaA 3 9B 11 12C 14 8Below C 12 3
Grades again In some situations where the expected cell
counts are too small, as in the case of the grades given
by Professors Alpha and Beta in Exercise 39, we can
complete an analysis anyway. We can often proceed after
combining cells in some way that makes sense and also
produces a table in which the conditions are satisfied.
Here we create a new table displaying the same data, but
calling D’s and F’s “Below C”:a) Find the expected counts for each cell in this new
table, and explain why a chi-square procedure is now
appropriate.
b) With this change in the table, what has happened to
the number of degrees of freedom?
c) Test your hypothesis about the two professors, and
state an appropriate conclusion.
Prof. Alpha Prof. Beta
A 3 9
B 11 12
C 14 8
Below C 12 3
Trending now
This is a popular solution!
Step by step
Solved in 4 steps with 2 images
