You might be wondering, what is statistics? Is it some complicated formula? Is it some goofy graph that you really don't know that much about?
When people refer to statistics, they're usually referring to information called data that's been collected and synthesized within a statistical study, and sometimes presented in a graphical form, like this.
While the image may be small and difficult to read, you get the idea that a LOT of information can be presented in the form of a graph.
It can also be presented numerically such as "The median household income in the United States is $46,326."
[MUSIC PLAYING] The practice of statistics deals with these four concepts here. Collect, analyze, interpret, and present. You begin by collecting information from a variety of sources. You then proceed to analyze that information that you've collected. After that, you interpret what that analysis means and then you present it in a way that anyone can understand. And in this course you're going to learn how to do all those things, and if I may try to be honest-- though as a robot, I can't fully experience the feeling of honesty-- I do understand statistics quite well.
And I must say it's a really neat way to describe our messy world. It's not pretty all the time, but statistics allow us a way to simplify things.
[MUSIC PLAYING]
Statistics is a neat way to describe a messy world. It's not pretty all the time. But statistics allows us a way to simplify things down.
When you use descriptive statistics, you are going to analyze what's going on at a particular point and use statistics to describe the information that you've obtained.
On the other hand, when you use inferential statistics, you are going to use statistics that you've obtained and make a generalization about the population at large.
IN CONTEXT
Let's say that you read the newspaper this morning and discovered that the average household income in the United States was reported to be $46,700.
This information didn't come from sampling every household in the United States. That wouldn't be realistic or feasible to knock on all the doors and speak to all those people. But someone arrived at this number. So, how did they get it?
Well, a sample was taken, and a generalization was made about the entire United States based on that sample.
This is inferential statistics.
Source: THIS WORK IS ADAPTED FROM SOPHIA AUTHOR JONATHAN OSTERS. bar chart, CC, https://en.wikipedia.org/wiki/Chart#/media/File:Black_cherry_tree_histogram.svg no modifications made