Praxis II Mathematics Content Knowledge Exam Prep

Answer: A - A piece of data that is atypical or significantly different from the rest of its data set is called an outlier. While true outliers are often easy to spot with critical thinking skills alone, there is also a mathematical precept for assessing these anomalies. Generally, a number that is two or more standard deviations from the mean is considered an outlier. In some cases, outliers can skew data significantly, which is why identifying them is critical. Occasionally, an outlier can be removed justifiably from a data set to improve the data's reliability.