Jaclyn shared this with me a long while ago.
1 = like tt person
0 = not interested at all
0.5 = half hearted
1 x 0 = 0 Hence no relationship will take place
1 x 1 = 1 The feeling is mutual.
1 x 0.5 = 0.5 Half the chance of getting together, coz one party will put in 100%
0.5 x 0.5 = 0.25 Saddest scenior, half hearted effort from each party, waiting for the other person to take some actions. In the end, they just wait for each other. How sad.