Paired or not paired ?

[Voltolini]

Dear friends, I understand that doing a before and after experiment is a good situation to use a paired design because you can measure the same individuals but.... I saw some examples considering the measuremente of the same area as a paired situation but, the individuals are not controled, so I can measure different individuals. So, the pair is not a couple of individuals but the two areas. Is it correct ? If you are measuring the individuals inside the two areas, it seems to me that I need to pair the individuals and not the areas ! I also read another example pairing the data because the two samples have genetic relatedness !   So... what is the correct logic of pairing ?     Thanks......     V.     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Prof. J. C. VOLTOLINI Grupo de Estudos em Ecologia de Mamiferos (ECOMAM) Universidade de Taubate, Departamento de Biologia Praca Marcelino Monteiro 63, Bom Conselho. Taubate, SP. CEP 12030-010. BRASIL. Tel: 0XX12 - 2254165 (Lab. Zool.) ou 2254277 (Depto. Biol.) E-Mail: [EMAIL PROTECTED] http://www.mundobio.rg3.net/ http://www.sobresites.com/ecologia/institui.htm ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~