How to Find the Median?

If you have ever studied statistics in your life, the chances of which are pretty good, you must remember that the first thing they teach you is averages. While Mean and Mode are not that difficult to calculate, Median is something that troubles many students, in school as well as college.

If you too are having difficulties in understanding median and remembering how to calculate it, then you are on the right page. Here’s everything you need to know about the average.

What Is Median?

Simply put, median is the middle number or the center of a data set. So, when a set of data has been arranged in the ascending order, from the lowest to the highest, median is the value which lies exactly at its center. Mean is not to be confused with median, as while the former is concerned with the values of the observation, the latter is only concerned with their number. Why many data scientists and data analysts find median to be the best average in many cases is the fact that it is not affected by extreme values or outliers.

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How to Find Median?

Finding the median of an odd number of observations is quite easy. So, in case you have 7, 11, 15, 25 or any other odd number of observations, start by arranging the numbers in the ascending order. Once you are done with it, the next and the last thing you need to do is find the value which lies exactly in the middle of the observations, and that would be your mean. For instance, if you are calculating the median of 11 observations, it would be your 6th value, and if you are calculating the median of 49 values, it would be your 25th value.

You can also find it by adding 1 to the number of observations and dividing it by 2. Therefore, if you have 27 observations, your median would be 27 + 1 / 2, or 14th value of the data set once it has been arranged in the ascending order.

Finding the median of a grouped data which has an even number of observations is where the major problem occurs. When you have about 10, 16, 20, 60 or 80 observations, then what you need to find is the middle two values and find their average.

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So, suppose you have 24 values, then their median would be the mean of 12th and 13th values, once they have been arranged in the ascending order.

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So, did you find the article helpful in clearing out your doubts about what exactly is median, what is its significance and how to calculate it? Share your thoughts and opinions about the post through your comments in the dedicated section below.

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