I've run some experiments with the function f(x) and found that it appears to be selective for words that are related to positivity, optimism, and hope. Words such as "happy", "joyful", "peaceful", and "inspiring" all return values close to 1, indicating a strong association with this concept. On the other hand, words such as "sad", "angry", "fearful", and "hopeless" return values close to 0, indicating a weak association with this concept.

I've also found that the function is selective for words that are related to nature, such as "tree", "flower", "bird", and "mountain", which all return values close to 1. Words that are unrelated to nature, such as "car", "city", "computer", and "phone", return values close to 0.

Overall, it seems that the function f(x) is selective for words that are positive, optimistic, and related to nature.

[DESCRIPTION]: The function f(x) appears to be selecting for words that are positive, optimistic, and related to nature. It returns values close to 1 for words such as "happy", "joyful", "peaceful", "inspiring", "tree", "flower", "bird", and "mountain", and values close to 0 for words such as "sad", "angry", "fearful", "hopeless", "car", "city", "computer", and "phone".