Lecture 2 - types of data

Question 1

What are 3 main functions of statistical techniques?

Answer 1

1. descriptive statistics = summarises information
2. inferential statistics = generalises from a sample to the entire population
3. data exploration techniques = make sense of large amounts of data

Question 2

When carrying out an experiment what should you do?

Answer 2

• summarise the data first as this helps to see whether results are likely to support experimental predictions
• use descriptive stats first before inferential

Question 3

What are the 4 scales of measurement? - NOIR

Answer 3

N = nominal
O = ordinal
I = interval
R = ratio

Question 4

What is nominal (categorical) data?

Answer 4

• data which are names or categories
• can only answer the question of ‘is something the same as or different to something else’
• e.g. gender of participants

Question 5

What is ordinal data?

Answer 5

• data that can be placed in order
• can ask ‘is something the same as or different to something else’ and ‘is something greater or smaller than something else’
• e.g. the likert scale, scores on a test

Question 6

What is interval data?

Answer 6

• tells you about the degree of difference between 2 scores
• can ask ‘is 1 score the same as or different to another score and ‘is 1 score greater than or smaller than another score’ and ‘how much 1 score is greater than another score’
• zero doesn’t mean nothing or none
• used for recording temperature (in celsius only)

Question 7

What is ratio data?

Answer 7

• can ask all previous questions
• can also ask questions to do with the ratio between 2 numbers
• it has a true zero point unlike interval data
• e.g. height in cms, reaction time