Estimator is the rule for calculating estimation. The normal distribution is the most important and most widely used distribution in statistics. The normal curve is symmetrical about the mean μ;The mean is at the middle and divides the area into halves;The total area under the curve is equal to 1;The Normal (Gaussian) distribution is completely determined by its mean and standard deviation σ (or variance σ2). The median estimator has an approximately normal distribution.
