Handling tag "weights"

Some of my documents have the following: "tag: [dog, animal, pets]". Is it possible to:

  1. influence index scoring based on score for each tag with something along "tag: {dog: 0.5, animal: 0.3, pets: 0.4}"

  2. influence search scoring for each word, so on "hello dog" I would decide that "hello" is 0.3 and "dog" is 0.8 (I believe this is hello^0.3, dog^0.8 in lucene)