APPENDIX B Making Sense of Data: A Statistics Primer

Question 1

What is meant by the term “False positive”

Answer 1

A “False positive” is when the result of a test suggests that a condition is present when it is in reality absent.

For example, a false positive in a pregnancy test indicates the female is pregnant when in reality the female is not pregnant.

Question 2

What is meant by the term “False negative”

Answer 2

A “False negative” is when the result of a test suggests that a condition is absent when it is indeed present.

For example, a false negative in a pregnancy test indicates that the female is not pregnant when in reality the female is pregnant.

Question 3

What are the five steps that comprise a biological study

Answer 3

1. Choose an experimental design
2. Collect data
3. Organise and visualise data
4. Summarise the data
5. Make inferences from the data

Question 4

What is meant by population in statistics

Answer 4

It is the study group of interest.

For example, if you were looking at a new treatment for a type of cancer then your population would be patients that have that particular type of cancer.

Question 5

What is meant by a quantitative variable?

Answer 5

A quantitative variable is one that can be expressed as a number.

Question 6

What are the two types of quantitative variable

Answer 6

1. Continous variable - variables that can be an infinite number of values such as temperature, weight, height and are obtained from using a measuring instrument like a ruler, balance etc.
2. Discrete variable - variables that can only take on whole numbers (1, 2, 3…) and are obtained by counting such as the number of students in a classroom, number of basketballs in a sports shop, number of red sweets in a jar.

Question 7

What is the opposite of a quantitative value and explain what is meant by this other kind of variable?

Answer 7

Categorical variable - A variable that is not expressed by numbers such as names of people, human blood type (A, B, AB, O).

Question 8

What is an ordinal value?

Answer 8

An ordinal variable is a type of continuous variable that has a normal ordering to it such as grades for a class test (A, B, C, D, F)

Question 9

State the name of the type of table shown below:

Answer 9

A frequency distribution table

Question 10

What is a histogram?

Answer 10

A histogram is a bar graph that shows us how frequent a particular class of data is.