Chapter 2: Processing and Representing Data

Question 1

What are databases?

Answer 1

Tables with a collection of data

Databases are a form of secondary data available online and often easily accessible.

Question 2

What is bivariate data?

Answer 2

Data with two variables

Two-way tables contain bivariate data.

Question 3

What can you calculate from tables?

Answer 3

Totals, differences, percentages

You can also describe trends and explain inconsistencies.

Question 4

True or False: Percentages in a table always add up to 100%.

Answer 4

False

This is often due to rounding errors.

Question 5

What is a pictogram?

Answer 5

Uses pictures or symbols to represent data

Each symbol represents a specific amount of data.

Question 6

What are the characteristics of simple bar charts?

Answer 6

• Bars of equal width
• Equal gaps between bars
• Frequency on y-axis

Simple bar charts display categorical data.

Question 7

What is the purpose of a key in a pictogram?

Answer 7

To show the amount each symbol represents

This ensures clarity in data representation.

Question 8

What do composite bar charts compare?

Answer 8

Different categories over time

They have single bars split into sections for each category.

Question 9

How are stem and leaf diagrams useful?

Answer 9

Organize data without losing detail

They show the shape of the distribution and retain original data.

Question 10

What does a population pyramid indicate?

Answer 10

Distribution of ages in a population

It can show proportions or percentages.

Question 11

What do choropleth maps represent?

Answer 11

Geographical areas shaded to indicate frequency

Darker shading indicates higher frequency.

Question 12

Define cumulative frequency.

Answer 12

A running total of frequencies

It helps in understanding data distribution.

Question 13

How do you calculate the median from a cumulative frequency diagram?

Answer 13

Divide total frequency by 2, then find on Y-axis

Draw a horizontal line to read off the value from the x-axis.

Question 14

What is the formula for frequency density?

Answer 14

Frequency / Class Width

Frequency density reflects concentration of values.

Question 15

What indicates the shape of a population distribution?

Answer 15

The shape of the population pyramid

An upright pyramid indicates a younger population.

Question 16

How to draw a pie chart?

Answer 16

Calculate angles for each frequency and ensure they add up to 360°

Label the sectors appropriately.

Question 17

What do comparative pie charts compare?

Answer 17

Two sets of data of different sizes

The areas should be in the same ratio as the frequencies.

Question 18

What do histograms represent?

Answer 18

Continuous data from grouped frequency tables

There are no gaps between bars.

Question 19

What is the significance of equal class widths in histograms?

Answer 19

They ensure uniformity in data representation

The x-axis represents data while the y-axis represents frequency.

Question 20

Fill in the blank: The _______ of a pie chart equals the total frequency.

Answer 20

Area

This helps in comparing different pie charts.

Question 21

What should you check when interpreting pie charts?

Answer 21

Proportions, not numbers

This helps in understanding the data representation accurately.

Question 22

What is the formula for Frequency Density (FD)?

Answer 22

FD = F/CW

F = frequency, CW = class width

Question 23

What should be labelled on the y-axis when drawing a histogram?

Answer 23

Frequency density

Question 24

How should the bars in a histogram be drawn?

Answer 24

Bars have no gaps in between

Question 25

What is the first step in estimating frequencies from histograms?

Answer 25

Calculate class widths and frequency density

Question 26

What is important to consider when calculating class width?

Answer 26

Some intervals may not include the entire bar

Question 27

What formula is used to work out the frequency for each bar?

Answer 27

FD X CW = F

Question 28

What must be the same when comparing histograms?

Answer 28

Class intervals and frequency density scales

Question 29

What should be described when comparing histograms?

Answer 29

The shape of the distribution and what it shows

Question 30

What are the possible shapes of a distribution?

Answer 30

Positive, negative, or symmetrical

Question 31

What are frequency polygons similar to?

Answer 31

Histograms with equal class widths but without bars

Question 32

How are points plotted in a frequency polygon?

Answer 32

Using mid-points of class intervals, then joined with straight lines

Question 33

What common error involves midpoints in frequency polygons?

Answer 33

Midpoints not used

Question 34

What is a common error in connecting points in frequency polygons?

Answer 34

Points not joined together with straight lines but with a curve instead

Question 35

What can make diagrams misleading?

Answer 35

Shape, axes, and scales

Question 36

What is a type of misleading diagram that uses the same symbol and size?

Answer 36

Pictograms

Question 37

What is a drawback of 3D charts?

Answer 37

They distort parts of the diagram

Question 38

How can colors make diagrams misleading?

Answer 38

Some colors may make parts stand out more, appearing more important

Question 39

What can happen if lines in a diagram are drawn too thick?

Answer 39

It becomes difficult to read information

Question 40

What is a misleading aspect of scales in diagrams?

Answer 40

Scales that do not start at zero

Question 41

What is another issue with axes in diagrams?

Answer 41

Axes that are unevenly scaled

Question 42

What is a common issue with axes that can mislead readers?

Answer 42

Axes that are not labelled

Question 43

Fill in the blank: Diagrams should use a _______ for clarity.

Answer 43

key