A sample is any subset of the total population. A representative sample is one that is chosen so that its characteristics are similar to that of the population.
A representative sample is a randomly selected subset of the population.
A panel study uses a representative sample, whereas a cohort study uses a sample with predetermined common characteristics.
What is the difference between commodity money and representative money
sample is a noun and sampling is TO sample(verb)
Set of units under study is populaltion and the subset of these units which is considered to be the representative of all units is the sample.
I believe the answer is in the names
What is the difference between the population and sample regression functions? Is this a distinction without difference?
random sample is a big sample and convenience sample is small sample
Many statistical statements for a population which are based on a sample are not valid if the sample is not representative.
a sample is a sample sized piece given... a sample size is the amount given in one sample
If measurements are taken for two (or more) variable for a sample , then the correlation between the variables are the sample correlation. If the sample is representative then the sample correlation will be a good estimate of the true population correlation.
Because without representative sample, your results will not be valid.