Phase 1 - Concepts and terminology of statistics applied to business decision-making 4-20 - Essay Example

Mean- the arithmetic mean (mean) of a list of numbers is the sum of all the members of the list divided by the number of items in the list. A classic example of Arithmetic mean is average income. The arithmetic mean may be misinterpreted to imply that most peoples income is higher than the case in fact is.” In statistics, mean has two related meanings: MEDIAN- The median is the number which is in the exact middle of the data set. Literally, it is the value in the middle. “The statistical median is the middle number of a group of numbers that have been arranged in order by size.

If there is an even number of terms, the median is the mean of the two middle numbers: If there is an even number of terms, add the two middle terms and divide by 2.”  (Statistical Median). Mode means the number that appears the most often, if working with only one variable. In statistics, mode means the most frequent value assumed by a random variable, or occurring in a sampling of a random variable. The term is applied both to probability distributions and to collections of experimental data.

Range - It means the difference between the highest and the lowest value. The range is the length of the smallest interval which contains all the data. It is calculated by subtracting the smallest observations from the greatest and provides an indication of statistical dispersion. The mid range point is the half way between two variables. .Variance -  In probability and statistics , the variance of a  random variable, is a probability distribution , a measure of its statistical dispersion , indicating how its possible values are spread around the expected value .

Where the expected value shows the location of the distribution, the variance indicates the scale of the values. A more understandable measure is the square root of the variance, called the Standard deviation. For a population, range is more than twice the standard deviation. Variance