Probably the box and whiskers plot, but there are others.
a graphic way to display the median, quartiles, and extremes of a data set on a number line to show the distribution of the data.
There are 5 quartiles in any data set.
It is marked by the minimum, and maximum, the median, as well as the lower and upper quartiles. It also shows the skewness of the data.
To find the inner quartiles (Q1 and Q3), first arrange your data in ascending order. Q1 is the median of the lower half of the data, and Q3 is the median of the upper half. The inner quartiles divide the data into four equal parts. The outer quartiles also known as the minimum and maximum values, are the smallest and largest values in the data set.
A cumulative frequency curve is a graph that shows the cumulative frequency of a data set. This type of graph can present data, such as medians and quartiles. Another name for this curve is an Ogive.
They are a simple measure of the spread of the data, which is not affected by extreme values.
It is a simple but crude measure of the spread of data.
Outliers
quartiles
Quartiles.
The quartile deviation(QD) is half the difference between the highest and lower quartile in a distribution.
Definately more than 4 pieces of data (intuitively, otherwise at least 2 of your quartiles will fall in exactly the same place as each other). But I think that's the only limit on how much data you need - there is no upper limit.