In a stem-and-leaf plot, the leaf will always only have one digit, and the stem will take the rest of the digit. No digit, or more than one digit in the stem? We could do the same with the second line to see that we also have scores of We could do this up to the last leaf on that line, to get golf scores from the first line of our plot of If we put the second leaf, ?7? ones, with the stem, we get ?67?, which is another golf score in our data set. So if we take the first stem, ?6? tens, and the first leaf, ?6? ones, we put them together to get ?66?, and that’s one golf score. They only make a data point when you put them together. In other words, the stem isn’t a data point on its own, and neither is the leaf. If the key had said ?6|6=606?, that would have meant that each stem represented the hundreds place (?6? would indicate ?600?), and the leaf would represent the units place (?6? would indicate ?6?).Įach leaf needs to be attached to the stem from the same row in order to give you each data point. ![]() This is a key, or legend, that tells us that we intended for the stem to represent the tens plane, and for the leaf to represent the units place. Notice that we also put “?6|6=66?” below the stem-and-leaf plot. ![]() In this plot, there are ?18? leaves, which means we collected ?18? golf scores. So if we want to know how many data points are in the set, we could count the number of leaves on the right side. The “ leaves” are all the other numbers on the right.Įach leaf represents one data point, in this case one golf score. First, the “ stems” are the numbers on the left, in this case the ?6? and the ?7?. Let’s use this particular plot to talk about what a stem plot shows. Putting people of similar age together in those groups would allow you to create a histogram with around ?10? bars, instead of a bar graph with around ?100? bars. That’s important to remember when making a histogram. Notice that each of these buckets is the same size or length. To create a histogram for the same information, you might group together ?0-9? year-olds, ?10-19? year-olds, ?20-29? year-olds, etc. In other words, your bar graph might have ?100? bars or more.Ī histogram is the perfect solution to an overly-complicated bar graph. In a typical bar graph, you have to show a bar for children younger than ?1?, another for ?1?-year-olds, for ?2?-year-olds, ?3?, ?4?, ?5?, all the way up to ?100? or maybe even older. For example, maybe you want to use census data to make a graph of the number of people of each age in the entire city of San Francisco. ![]() One reason you might want to use a histogram instead of a bar graph is because you have too many data points to plot individually. A histogram represents a continuous data set, which is why there are no gaps between the buckets. Unlike bar charts, histograms have no gaps between the bars (although some bars might be absent, which means there’s no frequency in that “bucket”).
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