In: Statistics and Probability
The sampling distribution of a statistic is the distribution of the statistic for all possible samples from the same population of a given size.The sampling distribution depends on: the underlying distribution of the population, the statistic being considered, the sampling procedure employed, and the sample size used. For example, consider a normal population with mean μ and variance σ. Assume we repeatedly take samples of a given size from this population and calculate the arithmetic mean for each sample. This statistic is then called the sample mean. Each sample has its own average value, and the distribution of these averages is called the “sampling distribution of the sample mean. ”
Sampling distributions are important in statistics because they provide a major simplification en route to statistical inference. More specifically, they allow analytical considerations to be based on the probability distribution of a statistic, rather than on the joint probability distribution of all the individual sample values.
A
RV is discrete if its range is finite or countable, and is
continuous otherwise.
In the continuous case the range is usually an interval, a
half-infinite interval like [0,∞) or the entire real line.
A continuous probability distribution (applicable
to the scenarios where the set of possible outcomes can take on
values in a continuous range (e.g. real numbers), such as the
temperature on a given day) is typically described by probability
density functions (with the probability of any individual outcome
actually being 0).
Continuous probability distribution: A probability distribution in which the random variable X can take on any value (is continuous). Because there are infinite values that X could assume, the probability of X taking on any one specific value is zero. Therefore we often speak in ranges of values (p(X>0) = .50). The normal distribution is one example of a continuous distribution.A continuous distribution describes the probabilities of the possible values of a continuous random variable. A continuous random variable is a random variable with a set of possible values (known as the range) that is infinite and uncountable. ... Thus, only ranges of values can have a nonzero probability.