Question

Does a margin of error imply that the research is not reliable? If an entire population is not surveyed, but rather just sampled, will results ever be 100% accurate?

Lastly, what does confidence level mean?

Answer 1

No, margin of error does not imply that the research is not reliable because there is always some probability associated with errors that is none of the experiment is 100% perfect it has some errors associated with it, but it depends on the researcher on how much error is acceptable in the experiment.

whatever level of error is acceptable is then considered to be the margin of error of the experiment.

Hence it cannot be said that a margin of error implies research is not reliable.

None of the samples of a population will 100% be accurate, to get 100% accuracy we willhave to study the whole population which in most of the cases is difficult or impossible.

Hence a sample is being studied and conclusions are drawn accordingly using that sample, although it won't be 100% accurate but if done properly it will surely tell most of the things about the population.

Confidence level is nothing but probability that the value of the parameter that is the population parameter will lie in the specified range.

In simple words if we estimate soe population parameter using sample of that population and give an interval where the population parameter must be lying then the interval is nothing but the confidence level of that population parameter.