Page 26 - THE MATHMATE November 2024

Student Handout

Kite diagrams are one way of presenting data – in particular, they help you to see trends in data in a
visual way. Kite diagrams are graphs that show density, number, or distribution along a transect
(distance). The “kites” allow researchers to easily compare the different frequencies of observed data
along the same transect. Larger kites meaning a greater frequency, and longer kites show wider
ranges along the transect. With several kites together on a graph, potential relationships between
different observations can be more easily identified.

Kite diagrams are very useful in biology, for example, when doing a study along a transect on a rocky
shore, biologists will take 1 square meter quadrat samples of organisms along a longer line (the
transect) leading from the beach to the top of the rocks. They can then compare population size and
density, or abundance, of different organisms. Zonation patterns become clear very easily when
graphing the data on a kite diagram.

In a kite diagram, the midline for each group in a diagram has a value of 0. The ‘kite’ is then drawn
symmetrically both above and below the line to represent your data. See example, next page.

How to Draw A Kite Diagram - Step by Step:

(1) Mark your x-axis. Make sure it is evenly spaced.

(2) Mark the y-axis. Count how many groups you have and count how many total squares along
the y-axis are on your graph paper.
o Divide the total number of squares by the total number of groups.
o Round to an even whole number.
o Draw a horizontal midline and place the group name on the midline.
o For example, if there are 20 squares per group, then 10 is the midline, and there are 10
squares above and 10 below the midline for each group. Draw the first midline at 10, the
second at 30, the third at 50, and so on. As another example, if you have six groups,
and 62 squares along the Y, then divide 62 by 6 (62 / 6 = 10.3, round down to 10). That
is 10 squares per group, with a midline at 5 squares up (and 15, and 25, and 35, etc).
Each group will have 10 squares, 5 above the midline and 5 below the midline. The
group name goes on the midline.

(3) Decide how many individuals are represented by each graph paper square.
Use this formula: (largest data point / 2) / # squares below midline; this allows you to put
half your data above the midline for the group and half below, making it symmetrical.
o Example 1: If the largest number is 86, and there are 5 squares below the midline, then
do this: (86 / 2) / 5 = 8.6. I could say each square represents 8.6 individuals, or I could
round up to 9 or 10 to make the calculations a little easier. Let’s say 1 square = 10
individuals.
o Then, if each square represents 10 individuals, to represent 43 individuals, you would
want 4.3 squares (43 / 10 = 4.3).
o Example 2: If you have 10 squares per group (5 below and 5 above the midline) and
your largest data number was 1200, then, first, divide 1200 by two (1200 / 2 = 600), and
then divide by 5 squares below midline (600 individuals / 5 squares = 120 individuals
per square). Each square would represent 120 individuals. If you have 430 individuals,
then you would need 3.6 squares to represent all of the individuals (430 / 120 = 3.6).

Scctm The MathMate 26 Volume 44/Number 1 October 2024