There is an important distinction between a sample of data and population of data. So, let’s take a research…

Data is set of observation. This observation can be collected in various ways such as field notes, survey or…

The Challenger disaster occurred on January 28, 1986, during the launch of the Space Shuttle Challenger. The Space Shuttle…

There are two main kinds of studies, observational studies and, experimental studies. The statistical process can be viewed in…

If you have a sample or population of data and you want to understand the different properties, the different…

Variance represents the average of the squared deviations from the mean. Because we square the deviations, the variance is…