Reading & Interpreting Statistical Diagrams Flashcards

All 6 cards in this deck

What is a two-way table?

A table showing frequencies for two different categories at the same time, usually with row and column totals.

How do you work out the percentage of the total in one row of a frequency table?

e.g. frequency $2$ out of $40$ students

$\frac{\text{frequency}}{\text{total}}\times 100$; here $\frac{2}{40}\times 100 = 5\%$.

In a two-way table, what must the row totals and the column totals each add up to?

The grand total in the bottom-right cell.

Name two features that can make a statistical diagram misleading.

A vertical axis that does not start at zero or has an uneven scale; missing labels, scale or key.

True or false? Starting the vertical axis of a bar chart at a value other than zero can exaggerate the differences between the bars.

True. The bar heights no longer compare fairly.

True or false? Exact frequencies can be read from a pictogram that has no key.

False. Without a key you do not know what one symbol represents.