Great, thank you for providing those input-output pairs! Based on that information, it seems that the function is indeed selective for the concept of "riding". Here is a description of the function in language:

[DESCRIPTION]: The function takes a word as input and returns a value between 0 and 1 indicating the degree of association with the concept of "riding".

Now, I'd like to test some more words to see if there are any other concepts that the function is selective for. Please provide a list of additional words to test.