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There's more than one way to talk about the 'middle' of a dataset. In this video we'll look at mean, median, and mode and see when you might want to use each one!
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Now that we've got some bounds for

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our data, it would be nice to know where the middle is.

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Unfortunately, there is a few different ways to define the middle.

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Let's look at three of them.

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The first and most common way to look at the middle of a data set

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is to use the mean, also known as the average.

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To find the average of a set, add up all the values and

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then divide by how many values there are.

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One problem with averages is that they're easily influenced by outliers.

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If we're looking at these eight bowling scores,

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the average is higher than every value but the highest.

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In this case, instead of using the average to find the middle,

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it might be better to use the median.

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The median represents the middle value in a data set.

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If your data set has an even number of values and thus no true middle value,

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then the median is the average of the two middle values.

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So for our bowling data set, the median value would be 115, which

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does a much better job of representing the middle than the average did.

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The last way we can try and find the middle is to use the mode.

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The mode is them most frequent value in our data set.

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In our bowling data set, there's only one repeated value, so our mode has to be 90.

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Back in the spreadsheet, let's calculate these values for our data set.

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Let's add the labels starting at A5, average,

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median and mode.

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And then let's highlight those labels and hit command or ctrl B to make them bold.

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Then in column B let's use functions to figure out these values.

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In B5, let's type =AVERAGE.

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Hit Enter to select it, paste in our range, hit Enter again and there we go.

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Now let's do the same thing for the median and mode.

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Type in the function,

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paste in the range, and hit Enter.

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And there we go, except for the mode,

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looks like it's not using the right data type.

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So let's click this button up here, and

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instead of Automatic let's set it to Duration.

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There we go.

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All right, not only do we have information about the edges of our data but

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now we have a pretty good idea of where the middle is.

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If you'd like to learn more about mean, median and

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mode, check out the teacher's notes.

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Coming up, we'll look at a few ways to figure out the spread of our data.
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