7CCSMASE
Tutorial 6 Solution
1. a)Studentnamecategories:{legalvalue,emptystring,non-emptyillegalvalue};
Student age categories: {legal value, value outside of the legal boundaries, not a number}
A-level grades categories: {legal value, a too low value, and value in illegal format}
Offered course categories: {legal value at NMS, legal value at King¡¯s but not at NMS, value in illegal format}
b) Representative values:
Student names: {
A-level grades: {AAA, ABB, ABBC}
Offered course: {01, 08, aa}
c) The number of tests to give full combinatorial coverage is 3 x 3 x 3 x 3 = 81
d) One error constraint can be ¡°Empty student name¡±. This already reduces the number of options for the student name category from three to two. Another error constraint can be ¡°Age not in the right format¡±, reducing the number of options for the age category from three to two. In total, the number of tests will then be 2 x 2 x 3 x 3 = 36 plus one test per each error constraint = 38 tests in total.
e)
Student name
Age
A-level grades
Offered course
John Smith
19
AAA
01
John Smith
5
ABB
08
John Smith
A
ABBC
aa
<> (empty)
19
ABBC
08
<> (empty)
5
AAA
aa
<> (empty)
A
ABB
01
John123
19
ABB
aa
John123
5
ABBC
01
John123
A
AAA
08
You can check that all pairs exist in the table, 9 tests in total.