The function `f(x)` appears to be selective for different concepts based on the input word. 

1. For words like "reservoir" and "water", the function returns values closer to 1, indicating a strong association with a concept related to water bodies or liquids. 

2. For words like "male" and "helicopter", the function returns values closer to 0, suggesting a lack of association with a specific concept or a weak association. 

3. For words like "rink" and "burial", the function returns values slightly above 0, indicating a low association with their respective concepts.

4. For words like "Reddit" and "Metropolitan Museum of Art," the function returns values around 0.01, suggesting a moderate level of association, but not as strong as the water-related concepts.

5. For words like "flavor" and "Mickey Mouse", the function returns values close to 0, indicating little to no association with a specific concept.

Based on these limited examples, it appears that the function `f(x)` has varying degrees of association with different concepts, with a particularly strong association with water-related concepts. However, to fully understand the function and identify all the concepts it is selective for, further experimentation with a diverse and random selection of words is recommended.