Why does SIMILARITY_EUCLIDEAN_DISTANCE only generates outputs with a similarity score of "1" for binary input?

[Thomas Söhngen]

Hello everyone,

I am calculating similiar items with the SIMILARITY_EUCLIDEAN_DISTANCE 
class. My input is binary data, users clicking a like button. The output 
only generates similarities with a similarity score of "1". It doesn't 
calculate all items similiar to each other, but for the items it finds a 
similarity, the output is always "1". Why is this?

I don't have the problem, when I also add a "dislike" information, with 
input lines "item_id,user_id,1" for a Like interaction and 
"item_id,user_id,-1" for dislikes. The similarity lies between 0 and 1 then.

Regards and thanks for suggestions,
Thomas