population and sample

[lordp...@gmail.com]

Hi,

my question is that should a sample always be a good representative of the population?

[Anand Iyer]

Yes.  It must be.

[Prakrit Sinha]

but must it always be a good representative? according to the sample definition  the sample is a subset of the population. can a not  a good representative of a sample be a sample nonetheless?

[Anand Iyer]

Sample is a sample of population, but one that represents the whole population.  When we talk about sample, we indirectly refer to a good representative sample.

Now, arguing whether that definition is acceptable can go endlessly.  

If you think in philosophical terms, all these concepts and terms are used to meet an end-goal - that's to solve problems.  If you're able to solve problems without accepting these conventions/rules, that's okay.  However, more than being just mere conventions/rules, they also help in forming a common language, that everyone can use to converse in.  If that's lost, then it's going to matters much harder.