Quota Sampling:

It  is  a form  of non-probability  sampling  in which  the researcher utilises some knowledge about the population  to  build some represkntativeness  into  the  sample plan. The population is divided into several subgroups according  to  the distribution  of population  in  these subgroups. Then, based  on the proportions  of  distribution  of population  in the  subgroups  the number  of sample units  from  each subgroup are selected. To  illustrate we  can take the known distribution in  the proportion. You know that women within reproductive age group 15-45 years  is 17% of  the population. Thus if you  are doing  an  opinion poll on family planning practices your sample should have 17% from the women  of 15-45 years.