Convenience  Sampling 
In  convenience  sampling  selection the researcher chooses the  sampling  units on the   basis of convince or  accessibility. It is  called  accidental sampling  because  the sample units enter by accident. This  is also known  as a sample of the man  in the  street i ,e selection of unit where they  are sample  units  are selected because  they are  accessible. For  example  in testing  a potential  new  product, the  sample  work  is done by  adding  the new  product to the appropriate shops  in the locality. Purchasing  and selling  of the  new product  is observed there.