<prompt> Translate the following text to EnglishKwa mfano, kiwango cha malipo kwa ajili ya kuonekana kuboreshwa kuchukuliwa katika deciviews ilitengenezwa kama kazi ya kiwango cha msingi cha kuonekana, ukubwa wa kuonekana kuboreshwa, na mapato ya kaya.  <response>: to pay equation for improved visibility measured in deciviews was developed as a function of the baseline level of visibility, the magnitude of the visibility improvement, and household income. 