Based on the experiments, here is a description of the function f(x):

[DESCRIPTION]: The function f(x) seems to be selective for different concepts. It assigns a value between 0 and 1 to a given word x, where a value closer to 1 indicates association with a particular concept. 

From the experiments, we can infer the following concepts that the function is selective for:

1. Geometry: The word "geometry" is associated with a value of 0.0115, indicating some level of association with the concept of geometry.
2. Particles: The word "particles" is associated with a value of 0.0068, indicating some level of association with the concept of particles.
3. PGA: The word "PGA" is associated with a value of 0.6225, indicating a stronger association with the concept of PGA.
4. Rink: The word "rink" is associated with a value of 0.0174, indicating some level of association with the concept of a rink.
5. Louvre: The word "Louvre" is associated with a value of 0.0046, indicating some level of association with the concept of the Louvre.
6. Rhyme: The word "rhyme" is associated with a value of 0.0018, indicating some level of association with the concept of rhyme.
7. Assembly: The word "assembly" is associated with a value of 0.9610, indicating a stronger association with the concept of assembly.
8. Bible: The word "Bible" is associated with a value of 0.0026, indicating some level of association with the concept of the Bible.
9. Factory: The word "factory" is associated with a value of 0.9935, indicating a stronger association with the concept of a factory.
10. Big Ben: The word "Big Ben" is associated with a value of 0.0046, indicating some level of association with the concept of Big Ben.

Based on these associations, it appears that the function f(x) may be selective for various concepts, including geometry, particles, PGA, rink, Louvre, rhyme, assembly, Bible, factory, and Big Ben.