Breadcrumbs Section. Click here to navigate to respective pages.

Chapter

Chapter

# Basic Statistics

DOI link for Basic Statistics

Basic Statistics book

# Basic Statistics

DOI link for Basic Statistics

Basic Statistics book

## ABSTRACT

Mathematicians, however, developed statistics, and statistics are needed for statistical quality control, statistical process control, and statistical trouble-shooting. The most common statistical tools are means and medians. Both give an indication of how data is centered. Range is the difference between the highest number and the lowest number in the data. Variance equals the sum of the squares of (each individual value subtracted from the mean) and then divided by (the number of the observations minus one.) Standard deviation (SD) equals the square root of the variance. When frequency distribution charts are plotted by a computer, they are usually arranged with the frequencies plotted horizontally and the measurements plotted vertically. Frequency distribution chart where: The data distribution is "normal", The number of observations is very large, The distance between points on the base of the curve is very small. Frequency distribution charts meeting all of these criteria are called normal curves because they are so common.