The Three Door Quiz Show Puzzle

The three door quiz show puzzle shows how wrong intuition can be when dealing with probabilities. A contestant in a game show may win a car by choosing which of three doors the car is behind. When you make your guess, the game show host opens one of the two doors you did not choose, […]

Continue Reading

Conditional Probability

Conditional probability questions arise when two possibly linked events,andoccur. We ask, given thathas happened, what is the probability thatwill happen? The equation we use is,the meaning of which is illustrated in the diagram below. What we are in fact doing by saying, ‘given thathas happened’ is excluding the possibility that will not happen. The diagram […]

Continue Reading

Combinations and Permutations – Examples

A choir consists of 13 sopranos, 12 altos, 6 tenors and 7 basses. A group consisting of 10 sopranos, 9 altos, 4 tenors and 4 basses is to be chosen from the choir. a) In how many different ways can the group be chosen? b) In how many ways can the 10 chosen sopranos be […]

Continue Reading

Coding

Coding is a method of transforming data so that the numbers are easier to manipulate. Numbers that are not too small and not too large are easier to work with, so if the raw data we start with consists of large numbers for example – and finding the standard deviation or variance will make them […]

Continue Reading

Contingency Tables

A contingency table is a tabular representation of data which falls into several categories. It shows frequencies, or less frequently, probabilities, for particular combinations of values of two qualities or discrete random variables X and Y. Each cell in the table represents a mutually exclusive combination of X-Y values. For example, consider a sample of […]

Continue Reading

Histograms

A histogram is a type bar chart using intervals on the x -axis, with the modification that the interval sizes are not fixed. The frequencies are defined by the areas of the bars, and the y – axis is not a frequency axis, but a frequency density axis. A histogram is better able to represent […]

Continue Reading