distinguish between point estimation and interval estimation.in what way latter is better than former?

Question

give the difference point and compare both

Answer 1

A point estimate is one specific number. Usually it's a value you got from a sample, but we're using that number to represent the whole population. For example, you may hear a TV announcer say that "the average American family has 1.4 children" with no further qualification. Obviously NO family has exactly 1.4 children, but presumably that number was the mean of a sample that was asked how many children they had.

An interval estimate says that the actual value for the population is within a certain range. That might be expressed as being between two numbers (like "normal" people of a given height are supposed to weigh somewhere between two figures), or it could be given as a number and a margin of error (like the results of poltical polls, where they say something like 55% plan to vote for Candidate X, plus or minus 3%).

The chance that the population figure is exactly the same as a point estimate is almost zero. However, the chance that it is in the range given by an interval estimate is very high (and can be predicted quite accurately). The interval communicates a lot more information and is more useful in making predictions.