There are five data values ranging from 82.5 to 99: 25%. There are five data values ranging from 74.5 to 82.5: 25%. There are six data values ranging from 56 to 74.5: 30%. Day class: There are six data values ranging from 32 to 56: 30%.Which box plot has the widest spread for the middle 50% of the data (the data between the first and third quartiles)? What does this mean for that set of data in comparison to the other set of data?.Create a box plot for each set of data.For each data set, what percentage of the data is between the smallest value and the first quartile? the first quartile and the median? the median and the third quartile? the third quartile and the largest value? What percentage of the data is between the first quartile and the largest value?.Find the smallest and largest values, the median, and the first and third quartile for the night class.Find the smallest and largest values, the median, and the first and third quartile for the day class.
The top 25% of the values fall between five and seven, inclusive. At least 25% of the values are equal to five. Twenty-five percent of the values are between one and five, inclusive. In this case, at least 25% of the values are equal to one. For example, if the smallest value and the first quartile were both one, the median and the third quartile were both five, and the largest value was seven, the box plot would look like: The right side of the box would display both the third quartile and the median. In this case, the diagram would not have a dotted line inside the box displaying the median. For instance, you might have a data set in which the median and the third quartile are the same. This video explains what descriptive statistics are needed to create a box and whisker plot.įor some sets of data, some of the largest value, smallest value, first quartile, median, and third quartile may be the same.
Approximately the middle 50 percent of the data fall inside the box. The first quartile marks one end of the box and the third quartile marks the other end of the box. The smallest and largest data values label the endpoints of the axis. To construct a box plot, use a horizontal or vertical number line and a rectangular box. We use these values to compare how close other data values are to them. A box plot is constructed from five values: the minimum value, the first quartile, the median, the third quartile, and the maximum value. They also show how far the extreme values are from most of the data. Recognize, describe, and calculate the measures of location of data: quartiles and percentiles.īox plots (also called box-and-whisker plots or box-whisker plots) give a good graphical image of the concentration of the data.Display data graphically and interpret graphs: stemplots, histograms, and box plots.