A Marketing Matrix is essentially a plot on a two-dimensional plane according to how well they meet customers’ key requirements.
You can do this by drawing two lines in the form of a cross. These two lines represent a continuum of bad to good performance for two benefits or attributes that are the most important in an industry.
For example, take computers. If the two most important things to customers are “performance” and “price” then, put the word “performance” at the top of, say, the vertical line and put the word “price” to the right of the horizontal line.
High performing computers would be plotted at the top of the vertical line, and low performing computers at the bottom of the vertical line.
Now, for each computer in the market you would plot where that computer fits on the performance line (compared to other computers) and on the price line.
One comment: A marketing matrix is essentially a perceptual map. You can read more about snake plots as a better way of doing this since a marketing matrix forces you to do this in 2 dimensions, and often more than two dimensions properly characterize a market.
Source : http://www.marketingprofs.com/