<Tr> <Td> ∝ </Td> <Td> ∝ (\ displaystyle \ propto \! \,) </Td> <Td> proportionality is proportional to; varies as everywhere </Td> <Td> y ∝ x means that y = kx for some constant k . </Td> <Td> if y = 2x, then y ∝ x . </Td> </Tr> <Tr> <Td> Karp reduction is Karp reducible to; is polynomial - time many - one reducible to computational complexity theory </Td> <Td> A ∝ B means the problem A can be polynomially reduced to the problem B . </Td> <Td> If L ∝ L and L ∈ P, then L ∈ P . </Td> </Tr> <Tr> <Td> ∖ </Td> <Td> ∖ (\ displaystyle \ setminus \! \,) </Td> <Td> set - theoretic complement minus; without; throw out; not set theory </Td> <Td> A ∖ B means the set that contains all those elements of A that are not in B . (− can also be used for set - theoretic complement as described above .) </Td> <Td> (1, 2, 3, 4) ∖ (3, 4, 5, 6) = (1, 2) </Td> </Tr> <Tr> <Td> </Td> <Td> (\ displaystyle \! \,) </Td> <Td> conditional event given probability </Td> <Td> P (A B) means the probability of the event A occurring given that B occurs . </Td> <Td> if X is a uniformly random day of the year P (X is May 25 X is in May) = 1 / 31 </Td> </Tr>

Is a mean the same as an average