A basic understanding of statistics can help students shine in different courses while earning a degree 100% online.
While there are fields in which statistics are used, such as accounting, finance, business analytics and information technology (IT), the topic will prove helpful in unexpected areas, such as psychology, sociology, criminal justice, healthcare — and even liberal studies!
Statistics can help make sense of large amounts of data. By applying statistical methods, students should be able to find patterns, identify trends and even make informed predictions about the future. Statistics can provide timely, useful information that leads to better, more reasoned decisions.
Statistics are often found in homework assignments: A reading about modern policing methods for a criminal justice class might use statistics when discussing the effectiveness of certain techniques.
While statistics might seem like a daunting field, the basics are quite simple, and the calculations can be performed easily on a calculator or simple spreadsheet. To get started with statistics, it’s important to know about measures of central tendency (a way to describe a set of numbers) and the difference between populations and samples.
Measures of Central Tendency: Means, Medians and Modes
To make sense of a set of numbers, students will need to know about means, medians and modes, which are collectively called measures of central tendency.
Consider this set of numbers: 1, 2, 2, 5, 14, 15, 17
- The mean is the number that results by adding all the numbers together and dividing the total by the quantity of numbers in the set. In this case, the sum is 56. When you divide the sum by the number of items in the set (there are 7 numbers), the mean is 8.
- The median is the number in the middle position of the set. Since there are 7 numbers, the fourth number is in the middle. That means the median is 5.
- The mode is the number that appears most frequently in the set. In this case, the number 2 appears twice and all other numbers appear once. So, 2 is the mode.
It is clear to see that this set of numbers produces a very different mean, median and mode. All three of these results are correct answers, so it’s very important to know what’s being requested. When people think of averages, what they’re usually referring to is the mean. However, a mean can be wildly skewed if there are a few exceptionally large or small numbers, so in some cases the median might better represent the set of numbers. And, in some cases, the mode might be the most useful answer.
Differences Between Populations and Samples
In statistics, it’s important to know the difference between a population and a sample. A population is an entire group under consideration, whereas a sample is just a portion of the population being measured. Since it’s practically impossible to measure every single item in a population, it’s necessary to use samples.
Here’s an example: A sociology student studying eating habits might want to know the average weight of all people in the United States. Is the research based on a population or a sample? The population for the research would be every single American — more than 320 million people! It would be out of the question to collect data for each person. Therefore, the research will be based on a sample, which is a cross-section of the population that can be measured.
Researchers must be careful to make sure the sample accurately reflects the population. Using the above example, the sample should have the same demographic characteristics as the country as a whole. If the researcher only looks at one gender, race or geographic region, the results from the sample might not be representative of the overall population.