1 : SAMPLING DISTRIBUTION (PART1)

- simple random sampling
- stratified random sampling
- cluster sampling
- multistage sampling
- systematic random sampling

(A) Mean : if the mean is calculated from the entire population of the data set then the mean is called population mean.

(B) Median : as the middle number when the data is arranged in order of size.

(C) Mode : the number which occurs most frequently [the most popular number].

(D) Variability : is a measure of how much data value differs from one another or equivalent, how widely the data values are spread out around the center.

(E) Range : is the simplest measure of distribution & indicates the "length" a distribution covers / it is determined by finding the difference between the lowest & highest value in a distribution.

(F) Interquartile Range : the difference between the third & first quartile and can be used to provide a measure of spread within a data set which includes extreme data values.

(G) Semi Interquartile Range : another measure of spread & is computed as one half of the interquartile range which contains half of the data values.

(H) Standard Deviation : the measure of spread most commonly used in statictics when the mean is used to calculate central tendency.

(I) Skewness : is a measure of the degree of asymmetry of a distribution.

(J) Kurtois : is a measure of whether the data are peaked or flat relative to a normal distributions.