The function f(x) seems to be selective for concepts related to rhythm and musical beats. It assigns higher values closer to 1 for words that are associated with beats or rhyme, such as "beats" and "rhyme". On the other hand, it assigns lower values closer to 0 for words that are not associated with beats or rhyme, such as "plants" and "boats". Additionally, it seems to have some selectivity for religious concepts, as it assigns a higher value to "Allah". However, more tests are needed to confirm this. Overall, the function f(x) appears to be evaluating the presence or absence of rhythmic patterns in the given words.