# Are 'complexity' and 'performance' countable or noncountable?

First of all, I am sorry to ask a question that is worth asking a lot of people, but I could not find an answer that was right for me, so I am posting a new question.

In many scientific journals, e.g., papers published by IEEE, the words 'complexity' and 'performance' appear very frequently. I also want to use these two words in my paper, but I am wondering whether to consider them as countable nouns or uncountable nouns.

According to many existing papers (searchable in google scholar), Sometimes they are used as being uncountable (e.g., We develop a blah-blah-blah scheme with low computational complexity; The performance of A and B schemes is blah-blah-blah.), sometime as being countable (e.g., We develop a blah-blah-blah scheme with a low computational complexity; The performances of A and B schemes are blah-blah-blah).

On the other hand, according to the Merriam-webster dictionary, the word 'performance' is defined as

Performance: how well someone or something functions, works, etc. : how well someone or something performs. (and there are both examples for 'count' and 'noncount')

Can I decide whether to use the above two words as a countable noun or a noncountable noun??? For example,

• 'To this end, we develop a heuristic algorithm with a low computational complexity.' vs 'To this end, we develop a heuristic algorithm with low computational complexity.'
• 'The algorithms developed in [3] and [4] have very high computational complexities.' vs 'The algorithms developed in [3] and [4] have very high computational complexity.'
• 'the performance of our proposed algorithm is better than those of other baseline algorithms.' vs 'the performance of our proposed algorithm is better than that of other baseline algorithms.'
• 'We compare the performances of our algorithm and the other baseline algorithms.' vs 'We compare the performance of our algorithm and the other baseline algorithms.'