When filing taxes in the US, the first thing the taxpayer is asked is whether somebody else can claim him/her as a dependent. What you have here is taxpayer NOT claimed as a tax dependent vs. taxpayer claimed as a dependent. Perfect example, I am a college student who is working part time, because I am receiving income I must file taxes HOWEVER, my parents pay for my college tuition and housing SO I am a taxpayer claimed as a tax dependent. A head of household, on the other hand, and as a general rule is not claimed as a tax dependent by anybody else therefore he/she is a tax payer NOT CLAIMED as a tax dependent by anybody else. So in the case of the student it would be a contribuyente incluido en otra declaracion de impuestos vs. contribuyente no incluido en otra declaracion de impuestos. I am not saying this should be your translation but just to give you an idea.
Please see:
https://www.taxact.com/support/1381/2016/standard-deduction-...