Steps organisations can take to quantify qualitative experiences by Anna Johansson via @infomgmt

Subjective experience tends to produce qualitative data if they produce data at all, which makes it notoriously hard to form the same calibre and a number of conclusions from those data.

I really like the three steps she suggests - numerical values for qualitative data is very important - it is efficient to create fields in the table or database, is a very efficient key for anything (be it a primary key or a foreign key) and can help you if you want to modularise code so that you can share it.