1. Lesson starter: types of correlation

2. Scatter graphs Monday, 14 March 2016 A scatter graph is used to try to find a relationship between two variables (things) Here is an example of how the information about AGE and AMOUNT OF MONEY SPENT AT THE WEEKEND is put onto a scatter graph. People were asked: What is your age? How much money did you spend this weekend? Their answers were recorded in a table like this:

3. I’m 18 and I spent £25 Age1816 Amount2510 I’m 16 and I spent £10

4. Age1816171518 Amount251022810 I’m 18 and I spent £10 I’m 17 and I spent £22 I’m 15 and I spent £8

5. Age18161715181719 Amount2510228101530 I’m 17 and I spent £15 I’m 19 and I spent £30

6. Age18161715181719 Amount2510228101530

7. This line is called the line of best fit. If it goes up in this direction, it has a positive correlation.

8. Age18161715181719 Amount2510228101530

9. 1.Plot these points on a scatter diagram. PupilABCDEFGHIJKLM Shoe S.2234576567432 Height1.31.51.4 1.51.81.71.6 21.31.51.3 a.What type of correlation does the scatter graph show between shoe size and height? b.What can you usually say about a the connection between shoe size and height?

10. Plot these points on a scatter graph to show the connection between revision and number of GCSE passes. PupilABCDEFGHIJKL Hours Rev. 45679734578341249768990 No. GCSE 4691052158910 a.Draw a line of best fit onto the scatter graph. b.Use this line to estimate how many hours are needed for 7 GCSE passes.