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Statistics can be appreciated by gaining a firm foundation in a few important pillars of understanding. First, there are two chief types of methods and second, it is important to note how variables are classed. Let us first start out with data. Data are plural and datum is singular. As an example, data (e.g., catheters per patient hospital admissions, dwell times, or cost savings) are distributed in different ways. One would look at the data to examine the issue being explored. For example, plotting catheters per patient admission on the horizontal axis (x-axis or abscissa) and the number of times it occurred (or frequency), you would have the shape (or distribution) of the data.
The shape of distributions is the main way statisticians make decisions of what statistical procedure they choose. There are essentially two types of statistical methods, parametric and nonparametric. Parametric statistical standards are...