One of the best features is it’s statistical capabilities So you can find outliers in Excel easily with simple statistics formulas.. For instance, the above problem includes the points 10.2, 15.9 , and 16.4 as outliers. The interquartile range is based upon part of the five-number summary of a data set, namely the first quartile and the third quartile.The calculation of the interquartile range involves a single arithmetic operation. $$ IQR = 647 - 517.5 = 129.5 $$ You can use the 5 number summary calculator to learn steps on how to manually find Q1 and Q3. i know there is a mathematical formula for it and i would use it but my teacher is hooked on finding everything through the calculator. i was doing a question for statistics and it stated a mean, standard deviation, possible outlier number. To find outliers and potential outliers in the data set, we first need to calculate the value of the inner fences and outer fences. Excel provides a few useful functions to help manage your outliers, so … Outliers are values which are far enough outside the "reasonable" variation of values in a data set that it makes sense to remove them for your calculations. the question asked to find out if the number was an outlier. When using Excel to analyze data, outliers can skew the results. One needs to calculate median, quartiles including IQR, Q1, and Q3. One setting on my graphing calculator gives the simple box-and-whisker plot which uses only the five-number summary, so the furthest outliers are shown as being the endpoints of the whiskers: Outliers make statistical analyses difficult. For example, my physics students will use a stopwatch to find out how long it takes a golf ball dropped from the roof of a barn to reach the ground. For example, the mean average of a data set might truly reflect your values. The interquartile range is what we can use to determine if an extreme value is indeed an outlier. An outlier is a value in a data set that is far from the other values. How to Find Outliers in Excel Excel has a lot of underused function that can greatly improve your data analysis. Outliers can be caused by experimental or measurement errors, or by a long-tailed population. This calculator performs Grubbs' test, also called the ESD method (extreme studentized deviate), to determine whether one of the values in the list you enter is a signficant outlier from the rest. Your graphing calculator may or may not indicate whether a box-and-whisker plot includes outliers. An outlier is a value that is significantly higher or lower than most of the values in your data. Said differently, low outliers shall lie below Q1-1.5 IQRand high outliers shall lie Q3+1.5IQR.