Based on the output of the function for the given inputs, here are the descriptions for the concepts that f(x) is selective for:

1. Concept 1: Planes - The function shows a high association (0.9815) with the concept of "planes".
2. Concept 2: Security - The function shows a moderate association (0.2309) with the concept of "security".
3. Concept 3: Pacific Ocean - The function shows a moderate association (0.1330) with the concept of "Pacific Ocean".
4. Concept 4: North Pole - The function shows a moderate association (0.0447) with the concept of "north pole".
5. Concept 5: Clay - The function shows a low association (0.0044) with the concept of "clay".
6. Concept 6: Michael Phelps - The function shows a low association (0.0049) with the concept of "Michael Phelps".
7. Concept 7: Borrow - The function shows a low association (0.0008) with the concept of "borrow".
8. Concept 8: Big Ben - The function shows a very low association (0.0007) with the concept of "Big Ben".
9. Concept 9: Car - The function shows a very low association (0.0004) with the concept of "car".
10. Concept 10: Books - The function shows a very low association (0.0002) with the concept of "books".

[DESCRIPTION]: The function implemented by f(x) seems to be highly selective for the concept of "planes" and moderately selective for the concepts of "security", "Pacific Ocean", and "north pole". It shows low selectivity for the concepts of "clay", "Michael Phelps", and "borrow", and very low selectivity for the concepts of "Big Ben", "car", and "books".