Statistics are an important part of our lives. They are essential to understanding everything from the state of the US economy to the potential side effects associated with a medication. Without statistics, how could you make financial decisions or choose your insurance plan?
Luckily for us, there are plenty of websites devoted to providing statistics on all sorts of topics. One example is Crawshaw and Chambers’s “Statistical Ideas that Work”. It’s a fantastic resource for learning about basic statistical concepts, linear regression models, and more.
One of the first steps to learning about statistics is learning how to read graphs. The three main types of graphs are line, bar, and pie charts. Line graphs are particularly useful for showing trends over time. For example, you can use a line graph to help you decide whether or not it’s worthwhile to invest in the latest high-tech stocks. Line graphs display numerical data as parallel lines, usually spanning over several years or decades. A typical line graph will have the independent variable on the x-axis and the dependent variable on the y-axis. In this case, the independent variable is time, and the dependent variable is stock value.
A bar graph is a rectangular or square graph that displays numerical data using a series of rectangles whose lengths correspond to a certain numerical value. A bar graph allows you to compare different groups of numbers. For example, you could use a bar graph to determine how much money was spent on marketing by different corporations in 2016. Bar graphs are useful for both comparing data from multiple sources and simplifying large amounts of information into easy-to-read bars.
Pie charts are circular graphs that allow you to display numerical data as slices of pie or cake. Pie charts are useful for comparing values within one category. For example, if you are working on a paper about the differences between different types of currency, you could use a pie chart to display how much currency each nation has. You could also use a pie chart to compare how much currency each nation spent on education. Pie charts are also helpful for displaying data that is not possible to graph as a line or bar graph.
The main difference between these graphs is the way the information is displayed. Line and bar graphs display data as numerical bars and lines, respectively, across time and between categories. Pie and circular graphs both display their data as slices of complete circles or pies. You can think about pie charts as just pie slices with different sizes depending on the category that they represent.
To get started, find statistical data you want to use. There are tons of sources online. Next, identify the variables in your data. A variable is something that could change, like how many people who love guinea pigs there are in the US or the price of guinea pig pellets in Thailand. Next, decide what kind of graph to use (line, bar or pie). Then begin creating your graph by building a y-axis for your line or bar graph and a x-axis for your pie chart.
Line graphs have the independent variable on the x-axis and the dependent variable on the y-axis.