Classifying and Representing Data

Question 1

Define

Random Sampling Method

Answer 1

Members of the population
have an equal chance of
being selected.

Question 2

Define

Stratified Sampling Method

Answer 2

Categories of a population are chosen, and members then are randomly selected from each category.

Question 3

Define

Systematic Sampling Method

Answer 3

Population is divided into a structured sample size. Members are then selected in a certain order from this structure.

Question 4

Define

Self-selected Sampling Method

Answer 4

Members of the population
volunteer themselves.

Question 5

Define

Categorical Data

Answer 5

Represents categories such as sex, colour etc. It may involve numbers, but these numbers have no mathematical meaning.

Question 6

Define

Nominal Data

Answer 6

Categorical data with a name that does not indicate order, for example “Male” and “Female”.

Question 7

Define

Ordinal Data

Answer 7

Categorical data that indicates order. For example your grade in a class may be “A”, “B”, “C”, “D” or “E”.

Question 8

Define

Numerical Data

Answer 8

Data that involves numbers (values). It indicates a quantity and can be used to perform calculations.

Question 9

Define

Discrete Data

Answer 9

Numerical data that involves whole numbers and is usually found by counting - for example, a carpark might have 3 holdens, 5 fords etc

Question 10

Define

Continuous Data

Answer 10

Numerical data that can involve decimals/fractions and is usually found by measuring - for example, heights.

Question 11

Define

Pareto Charts

Answer 11

These charts use categorical data and combine a frequency histogram with a cumulative frequency percentage line graph.
The histogram is plotted in descending order from the left, with the scale on the left hand side. The cumulative frequency percentage polygon is superimposed over this with its scale on the right hand side.

Question 12

How do you make a Pareto chart?

Answer 12

1. Draw the horizontal axis and place each category on the horizontal
   axis in order of frequency.
2. Find the cumulative frequency and cumulative percentages
   for each category.
3. Draw the frequency histogram with an appropriate vertical axis on the
   left-hand side.
4. Draw a cumulative percentage line graph with the vertical axis on
   the right-hand side.
5. Construct a legend for both the histogram and the line graph.