Statistics are of monumental importance. They are used to analyze large bodies of collected data in order to break them down into simpler, more readily usable forms through charts and graphs and for drawing conclusions about larger populations from smaller samples. Statistics are of two main types – descriptive and inferential. Descriptive statistics basically collects data from a particular sample and summarizes it.
Concerning inferential statistics, Siddharth Kalla and Lyndsay T Wilson in an article reproduced on Explorable explained that inferential statistics attempts to relate the outcome from one experimental study to more general populations. In effect, it attempts to provide answers to questions about populations and samples that were excluded from the test, in a given experiment. The goal of any survey is to apply the conclusions drawn from the survey to the general population. This assumes that the sample size is sufficiently large and the selected sample sufficiently represents the population for which the sample is tested. This is crucial to inferential statistics, as the aim is to be able to say something accurate and conclusive about the general population.
When claims are made about the outcome of a certain activity these claims can usually be verified by using two groups, one on which the activity is performed as a test and the other being the control group (on which the test is not performed). Starting points or baselines of similar weight would have first been established for the two groups. The outcome of the activity (the test) for the group on which the test was performed will then be measured and compared to that group’s baseline. If the results of the test for the test group shows an improvement from the baseline, this is of statistical significance. If it is concluded that the activity resulted in the improved outcome and this outcome can be applied in general and for all people, this is inferential statistics.
eCornell’s Professional Certificate in Business Statistics covers several key topics, including inferential statistics. This is offered in the Data Science program.