Statistics

Question 1

Five reasons bias can occur in data

Answer 1

Sample size is too small
Dishonest answers
Using misleading or unclear questions
Low response to the survey 
Identifying  the incorrect population group

Question 2

Give two advantages to online surveying

Answer 2

Cheap to make

Fast results

Question 3

Give two disadvantages to online surveying

Answer 3

Technical problems

Limited to those who have access to a computer.

Question 4

What is a questionnaire

Answer 4

Aset of questions used to obtain data from a population.

Question 5

Give five principles of a good questionnaire

Answer 5

Simple language
Use of yes or no answers as is easier to analyse
Represent the questionnaire topic
Have not got influencing or persuasive language

Question 6

What is the data handling cycle

Answer 6

Ask questions, collect data, analyse it, interpret results

Question 7

What is primary data

Answer 7

Data we collect first hand

Question 8

What is secondary data

Answer 8

Data collected by others eg. Internet, papers, books

Question 9

Explain Numerical and Categorical data

Answer 9

Numerical data is measured in numbers ex. Shoe size

Categorical data is opinion on a subject ex. Colours

Question 10

What are the two different types of numerical data

Answer 10

Continous- infinite values ex. Height

Discrete- finite values ex. Family size

Question 11

What are the two different types of categorical data

Answer 11

Nominal- Cannot be ordered ex. Opinion

Ordinal- Can be ordered ex. months of the year

Question 12

Give an advantage to a mean of data

Answer 12

Calculated using all data

Question 13

Give disadvantages to a mean of data

Answer 13

Influenced by extreme values

Only used for numerical data

Question 14

Give advantages to a mode of data

Answer 14

Easy to calculate

Not effected by extreme values

Question 15

Give disadvantages to a mode of data

Answer 15

Need a large sample

Can have more than one mode

Question 16

Give advantages to a median of data

Answer 16

Easy to get

Not effected by extreme values

Question 17

Give disadvantages to a median of data

Answer 17

Only takes data order but not value into account

Question 18

Give advantages to a range of data

Answer 18

Easy to calculate

Question 19

Give disadvantages to a range of data

Answer 19

Only for numerical data

Influenced by extremes

Question 20

Name six types of graph

Answer 20

Line plot
Bar chart
Stem and leaf
Back to back stem and leaf
Pie chart
Histogram

Question 21

What is an outlier

Answer 21

Item of data that lies far away from the pattern in the rest of the data

Question 22

Explain what simple random sample means

Answer 22

Each unit of the population has an equal chance to be chosen

Question 23

What is the distribution of data

Answer 23

List of all values a variable takes