Question

Suppose for any class in a university, one expects 50% of the students to have grade
equal or above B+, while the remaining students to be below B+. Now in one class of 20
students, eventually there are 12 students having grade equal or above B+, while the remaining
8 students are below that. How well does the observations fit the expectation? Using the
goodness-of-fit chi-square test to give a p-value.

Answer 1

in a chi square test  $\chi ^2=\sum (O-E)^2/E$

Given data N 20 P50 tudents below obsoved Valuesto) ase 12, Null Vu)pothesis o-os 、 S, gn,カCan ( @ -- Co-E o'나 2 12 I 0 0.4 1 0 0.8

Decision ulat d n- 2- at di oos Arom ct Но, it iS mot sgracant at sy.eue The obsewaons fit the expectation