What are the whiskers in a box plot?
The whiskers are the two lines outside the box, that go from the minimum to the lower quartile (the start of the box) and then from the upper quartile (the end of the box) to the maximum. The graph is usually presented with an axis that indicates the values (not shown on figure 4.5.
How are box and whisker plots used in the real world?
You can use “box and whisker plot” in the real world to when you are trying to compare something with another. For example if you want to compare which phone is worth it, you can do this by getting the average of how many people buy the better phone.
What is the first step to create this box and whisker plot?
The first step in constructing a box-and-whisker plot is to first find the median (Q2), the lower quartile (Q1) and the upper quartile (Q3) of a given set of data. You are now ready to find the interquartile range (IQR). The interquartile range is the difference between the upper quartile and the lower quartile.
What are upper and lower whiskers?
The whiskers each cover 25% of the data values. The lower whisker covers all the data values from the minimum value up to Q1, that is, the lowest 25% of data values. The upper whisker covers all the data values between Q3 and the maximum value, that is, the highest 25% of data values.
How do you read a box and whisker chart?
At the ends of the box, you” find the first quartile (the 25% mark) and the third quartile (the 75% mark). The far left of the chart (at the end of the left “whisker”) is the minimum (the smallest number in the set) and the far right is the maximum (the largest number in the set).
How do you find q1 and q3 in a box-and-whisker plot?
The first quartile is the median of the data points to the left of the median. The third quartile is the median of the data points to the right of the median. Step 4: Complete the five-number summary by finding the min and the max.
Why is it called a box-and-whisker plot?
In addition to the box on a box plot, there can be lines (which are called whiskers) extending from the box indicating variability outside the upper and lower quartiles, thus, the plot is also termed as the box-and-whisker plot and the box-and-whisker diagram.
How do you read a box and whisker graph?
When the median is in the middle of the box, and the whiskers are about the same on both sides of the box, then the distribution is symmetric. When the median is closer to the bottom of the box, and if the whisker is shorter on the lower end of the box, then the distribution is positively skewed (skewed right).
How do you describe the shape of a Boxplot?
In its simplest form, the boxplot presents five sample statistics – the minimum, the lower quartile, the median, the upper quartile and the maximum – in a visual display. The box of the plot is a rectangle which encloses the middle half of the sample, with an end at each quartile.
Where is Q3 on a box plot?
Q3 is represented on a boxplot by the right hand edge of the “box”. Q3 is approximately 12 in this graph. Step 3: Subtract the number you found in step 1 from the number you found in step 3. This will give you the interquartile range.