Statistical testing:the sign test

Question 1

what is statistical testing?

Answer 1

statistical testing provides a way of determining whether a hypothesis should be accepted or rejected
- By using a statistical test, we can find out differences between variables and if they are significant or have occurred by chance

Question 2

What is the criteria for a sign test?

Answer 2

1. we need a difference and not an association
2. we need to use a repeated measures design
3. we need nominal data

Question 3

How do we conduct a sign test?

Answer 3

1. State the null and alternative hypothesis
2. Record the data and work out the sign overall. This will either be positive or negative
3. Find the s value which is the less frequent sign
4. Find the critical value. If the critical value is greater than the significant value, reject the null hypothesis

Question 4

What is probability?

Answer 4

• This refers to the likelihood that certain events will occur.
• By investigating probability, we can determine whether the null hypothnesis is true or if the alternative hypothnesis is.

Question 5

What are the three factors that influence the statistical test?

Answer 5

• difference or correlation
• Experimental design
• Level of measurement

Question 6

What are the different experimental designs?

Answer 6

• there are three experimental designs which are independent groups, repeated measures and matched pairs
• Independent groups = unrelated as each condition is different
• repeated measures + matched pairs = related designs as each condition is the same

Question 7

What are the different levels of measurement?

Answer 7

• ordinal data
• nominal data
• interval data

Question 8

What is nominal data?

Answer 8

• Data is organised into categories.
• For example, they would be organised into either yes or no
• nominal data is discrete as one item can appear in each category

Question 9

What is ordinal data?

Answer 9

• This is data organised in a specific way
• For example, rating how much people like psychology from 1-10.
• Ordinal data does not have equal intervals as someone who likes psych and rates it a 10 may not like it double as someone who rated it as 5
• This is because ordinal data is subjective

Question 10

What is interval data?

Answer 10

• interval data is based on numerical data including precisely defined units

Question 11

Draw out the table of tests/ what acronym?

Answer 11

carrots should come mashed with sweetcorn under roast potatoes

Question 12

What category does chi - sqaured fall under

Answer 12

• it is a test of difference or association
• the design is unrelated
• the data is norminal

Question 13

what does mann - whitney fall under?

Answer 13

• unrelated design
• ordinal data