Mean, Median, and Mode

Key Concepts

Review core concepts you need to learn to master this subject

Mean of a Dataset

The mean, or average, of a dataset is calculated by adding all the values in the dataset and then dividing by the number of values in the set.

For example, for the dataset [1,2,3], the mean is 1+2+3 / 3 = 2.

Mean

Lesson 1 of 3

1
Finding the center of a dataset is one of the most common ways to summarize statistical findings. Often, people communicate the center of data using words like, on average, usually, or often….
2
The mean, often referred to as the average, is a way to measure the center of a dataset. The average of a set is calculated using a two-step process: 1. Add all of the observations in your da…
3
While you’ve shown that you can calculate the average yourself, it becomes time-consuming as the size of your dataset increases — imagine adding all of the numbers in a dataset with 10,000 ob…
4
In this lesson, you learned how to calculate the average of a dataset using the formula: \bar{x} = \frac{x_1 + x_2 … + x_{n}}{n} and the NumPy function: np.average(my_array) — Circling back…

1
In this lesson, you will learn how to find the median of a dataset — a common measure of a dataset’s center. Each of the next three exercises will cover the following topics: - Manually fin…
2
The formal definition for the median of a dataset is: *The value that, assuming the dataset is ordered from smallest to largest, falls in the middle. If there are an even number of values in a dat…
3
Finding the median of a dataset becomes increasingly time-consuming as the size of your dataset increases — imagine finding the median of an unsorted dataset with 10,000 observations. The Nu…
4
In this lesson, you learned how to find the median of a dataset in two steps: 1. Sort the dataset 2. Identify the one or two numbers that fall in the middle of the sorted dataset You also learned …

1
In this lesson, you will learn how to find the mode of a dataset. Each of the next three exercises will cover the following: - Manually finding the mode of a dataset - Using Python’s SciPy librar…
2
The formal definition for the mode of a dataset is: *The most frequently occurring observation in the dataset. A dataset can have multiple modes if there is more than one value with the same maxim…
3
Finding the mode of a dataset becomes increasingly time-consuming as the size of your dataset increases — imagine finding the mode of a dataset with 10,000 observations. The SciPy stats.mode…
4
In this lesson, you learned how to find the mode of a dataset in two steps: 1. Find the frequency of every unique number in the dataset 2. Determine which number has the highest frequency You also…

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