Binary variables([0, 1], or [true, false]) contingency table for binary data Row 10 sum 6 a+b Row i d c+d sum a+c b+d Simple matching coefficient btc +6+c+d Invariant of coding of binary variable: if you assign 1 to pass"and 0 to fail or the other way around, you'll get the same distance value 55 Binary Variables ({0, 1}, or {true, false}) ◼ A contingency table for binary data ◼ Simple matching coefficient ◼ Invariant of coding of binary variable: if you assign 1 to “pass” and 0 to “fail”, or the other way around, you’ll get the same distance value. a b c d b c d i j + + + ( , )= + sum a c b d p c d c d a b a b sum + + + + 0 1 1 0 Row i Row j