<prompt> Translate the following text to EnglishKwa wengine, sampuli ya nasibu ni muhimu kwa utafiti wa kesi, masomo ya kesi ni utafiti usio wa kawaida ambao unachunguza hali bila upendeleo, ambapo tunaweza kuangalia idadi ndogo ya kesi ambazo zingewakilisha ulimwengu kwa ujumla, na ukaguzi wa hali husika katika mazingira maalum bila jaribio la kuelekeza ulimwengu mkubwa.  <response>: To others, a random sample is necessary for a case study, case studies are nonnormative research that investigate a situation without prejudice, where we could look at a limited number of cases that would represent the universe overall, and a review of relevant conditions in a specific environment with no attempt to project to a larger universe. 