Correlation

Question 1

What are the variables called in a correlation and is there an iv or dv?

Answer 1

They are called co variables (always needs to be expressed as a number and each p much have 2 separate ordinal level numbers) and there is no iv or dv

Question 2

What would be a research aim for a correlation

Answer 2

To investigate whether there is a relationship between sunshine and happiness/ are they related rather than to investigate whether sunshine is a cause of happiness (in an experiment)

Question 3

An example of a two tailed correlational hypothesis

Answer 3

There will be a significant relationship between co variables x and y

Question 4

Example of a one tailed correlation also hypothesis

Answer 4

There will be a significant positive/negative relationship between co variables x and y

Question 5

Example of a null correlational hypothesis

Answer 5

The will not be a significant correlation between co variables x and y any relationship will be due to chance factors

Question 6

What are the advantages of correlation studies

Answer 6

1. Although don’t carry out collection of new data, they tell us something new (can tell us if two co variables are related also strength and direction of relationship 2. Useful technique when either practical or ethical reasons mean variables cannot be manipulated E.g accidents and alcohol consumption 3. Be a good starting point for research as more research can investigate links further

Question 7

Disadvantages of correlational studies

Answer 7

1. Don’t tell you anything about cause and effect 2. Inferential statistical tests will not always pick up on a relationship between two co variables 3. Do not require the collection of qualitative data so hard to tell meanings behind

Question 8

What descriptive stat is used for correlation, how to make one and the things to remember

Answer 8

A scatter graph. Each axis should start from 0., precise title that relates to a relationship, Each cross represents a PAIR of values (total number of crosses is the size of data). Draw a line of best fit only if required. Scattergraph doesn’t justify x caused y- just a relationship, or that a hypothesis can be rejected or kept as can only be done with inferential stats. Findings: raw data e.g mean median mode conclusions: inferences you can make from data e.g direction and strength

Question 9

What inferential statistical test is used for correlation and what the results mean

Answer 9

Spearman’s rho which calculates a correlation co efficient between -1 and +1. + is a positive correlation, - is negative and one around 0 e.g 0.12 or -0.17 is no correlation. The further from 0 the correlation is the stronger it is (-1 perfect -, -0.75 strong -, -0.5 moderate -, -0.25 weak -, 0 none, and same on other side) lines on graph look like back slash to jumble in middle to forward slash