A representative sample.
Random selection.
representative
The fact that the data are from a representative sample is irrelevant. What matters is the nature of the data that you have and the message that you want to convey to your viewers. If the data are qualitative then a bar or pie chart are probably the most appropriate. If they are quantitative, then any type of chart may be appropriate. It depends on the variables. If there are several observations on each member of the sample, then a stacked bar chart may be the right thing.
The sampling error is the error one gets from observing a sample instead of the whole population. The bigger it is, the less faith you should have that your sample represents the true value in the population. If it is zero, your sample is VERY representative of the population and you can trust that your result is true of the population.
Because without representative sample, your results will not be valid.
It is important for a sample to be representative, so that the whole population's view is counted, and not biased by one particular group within the population.
To generalize results from the sample population to the target population.
It helps you nawser
If the sample is not representative of the population, then the characteristics of the sample are not the characteristics of the population. Example: If I want to estimate the percentage of the population that are men, and my sample is the school's football team, my estimate would be that 100% of the population is comprised of men. What went wrong with my survey ? Simple. The football team is not a representative sample of the population, at least not as regards gender.
A representative sample is a randomly selected subset of the population.
A simple random sample.
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.
It is called a representative sample.
A sample that accurately reflects the characteristics of the population as a whole
biopsy
That the key characteristics of the population are reflected in the sample.