Tufte's data density, readability and comparison

1. What does Tufte suggest about the proportion of presentation graphics?
2. What is data density in visualization?
3. What is data-ink ratio?

What does Tufte suggest about the proportion of presentation graphics?

Tufte claims that good graphical representations maximize data-ink and erase as much non-data-ink as possible. He put forward the data-ink ratio which is calculated by 1 minus the proportion of the graph that can be erased without loss of data-information.

What is data density in visualization?

1. Don't use graphs to display small amounts of data. Good graphics is proponent of high data density. Data density is defined as the ratio of the number of entries in a data matrix to the area of the data graphic.

What is data-ink ratio?

Tufte defines the data-ink ratio as the amount of data-ink divided by the total ink required to print the graphic. In a layman term, Tufte suggests removing those elements that don't add new information to the graphic, i.e., using less ink (chart elements) is more effective, attractive, and imperative for viewers.