==Difference between Population and Sample==
===Accuracy/=Validity and Precision/=Reliability===
{|class="wikitable"
|+Definition
|-
!Accuracy = !!Validity
|
*Closeness of observed values '''to true population values'''
**AKA 'Trueness'
|-
!Precision = !!Reliability
|
*Closeness of observed values '''to each other among sample'''