Matrix Charts

Matrix Charts can organize large amounts of information

A compare and contrast chart works well when comparing two items – like the cat and the dog _ and can occasionally be used with a third item. But if, for example we have a cat, dog and horse, we need spaces descriptions that apply to all three, to the cat and dog, the dog and horse, and the cat and horse plus the three spaces for what applies to only one. It isn’t worth the trouble.

I have often described the matrix chart (or simply, the chart) as an advanced compare and contrast chart. It certainly helps you prepare for compare and contrast test questions. The chart below should be more or less familiar to every student who has studied biology.

When I was a students there were five classes of vertebrates: fish, amphibians, reptiles, birds, and mammals. Now, depending on where you look there are 5, 6, 7, or maybe more. All the differences are with fish. They once were all in a single class. Now they are divided.

1. Class Agnatha: the lampreys, have cartilage instead of bones and no movable jaws.
2. Class Chondrichthyes: the sharks, rays, skates and saw fish have cartilage but do have movable jaws.
3. Class Osteichthyes: the bony fish include the many varieties of familiar fish: tuna, trout, salmon, etc.

For the purposes of this chart, I will group them all under the category of fish.

For a proper compare and contrast chart, I need to list characteristics that are true for all of them. With a matrix, there is no space for this, so I will list them separately:

All vertebrates have:
1. A well-developed backbone with vertebrae
2. A well-developed nervous system with brain, spinal cord, and well-developed sensory organs.
3. A defined head, paired appendages (usually), muscles attached to bones, and a closed circulatory system.

Five classes of vetebrates are compared in a detailed chart or matrix.

With this kind of chart, you can study the details vertically, considering one class at a time. You can also study the details horizontally, comparing the same system across all five classes of vertebrates. I usually read and record information to fill in the chart vertically. Then I studied the information horizontally.

As you study, imagine possible compare and contrast questions.
Compare fish and amphibians.
Compare the respiratory systems of the fish, amphibians and reptiles.
Compare the reproductive systems in all groups of vertebrates.

Using a Matrix with far more information

I used a chart very similar to this for a class in Invertebrate Zoology. The Invertebrate chart covered 34 Phyla with varying numbers of classes in each. The chart covered an entire wall.

Here I used 8 categories, in the Invertebrate chart I had about 15 categories.

How did I study this massive amount of information? I looked horizontally for groups that were the same in one category and circled these areas. I located places where there was a major evolutionary development. In this chart that might be changing from cold to warm-blooded. It could have been the change from eggs to live births. I marked these with a bright marker.

Then, I rehearsed the information horizontally. One day I would practice the digestive system from simple animals like sponges and jellyfish to more complex ones like the octopus. With major turning points marked, it was fairly easy to picture the chart in my mind. I might say

“With the digestive system, these animals had no mouth, the particles flowed in through pores and were filtered out and absorbed where they were. This group had one opening, food went in, was digested, and the wastes went out the same opening. A major change occurred when the digestive system had two openings, a mouth of intake, and an anus for pushing out waste materials.”

Another large matrix I remember was for a book on 50 famous educators. I needed to learn their opinions or what they recommended on a variety of topics… different for different educators.  I listed the 50 names across the top and the topics down the side. I only filled in the spaces if this book described their opinion on that topic (like schools should prepare students with skills for work or students should study the classics)  I pretty much ignored secondary ideas and focused on topics the educator was best-known for. I also looked for topics where the book included educators strongly for and strongly against an idea. I knew that test questions of comparison would probably be ontopics like these.

The greatest advantage of these charts is that you can first learn the information vertically, and then study the material horizontally – looking for major similarities and differences.

How can you use a matrix to organize data?

From my personal examples, you can see it is most helpful when you are studying a large number of topics that are divided into a number of categories. Here are several examples.

Plays of Shakespeare (or literature by other authors)  divided into setting (place and time), main characters, plot, category (comedy, drama, tragedy, etc) memorable quotations, etc.

Countries of South America looking at the government, famous people, important exports, capital city, population, or whatever information you might be interested int.

A list of senators or candidates running for office and their positions on a number of controversial issues.

If you haven’t read Compare and Contrast, you might find that helpful.

Leave a Reply