rsion":"gemini-3-flash-preview"}},{"id":"e5a283fd-4354-49a2-9aac-4f4ab046c32a","label":"c","content":"The equation of the regression line is $w = 1.37h - 173$\n\nGive an interpretation of the gradient of this regression line.","markscheme":"- For every 1cm increase in height weight increases by 1.37kg B1","marks":1,"order":2,"markingRubric":{"totalMarks":1,"points":[{"id":"p1","marks":1,"description":"Correctly interprets the gradient as the weight increase per unit height increase.","code":"B"}],"finalAnswers":[],"generatedAt":"2026-05-12T02:14:06.542Z","modelVersion":"gemini-3-flash-preview"}},{"id":"4e8f9d92-80fc-44cc-ad98-ec28cfffc903","label":"d","content":"Use the equation of the regression line to estimate the weight of a player who is 170cm tall.","markscheme":"- $w = 1.37(170) - 173$ M1\n- $w = 59.9$ kg A1","marks":2,"order":3,"markingRubric":{"totalMarks":2,"points":[{"id":"p1","marks":1,"description":"Substitution of $h = 170$ into the regression equation.","code":"M"},{"id":"p2","marks":1,"description":"Final answer of 59.9.","code":"A"}],"finalAnswers":["59.9"],"generatedAt":"2026-05-12T02:14:06.542Z","modelVersion":"gemini-3-flash-preview"}},{"id":"e4f9d17d-a640-45e2-92de-671e0a7b7120","label":"e","content":"Comment on the reliability of your estimate in part (d), giving a reason for your answer.","markscheme":"- It should be reliable. 170 is within the range of data and the additional person is also a football player. B1","marks":1,"order":4,"markingRubric":{"totalMarks":1,"points":[{"id":"p1","marks":1,"description":"States it is reliable because 170 is within the range of the data (interpolation).","code":"B"}],"finalAnswers":[],"generatedAt":"2026-05-12T02:14:06.542Z","modelVersion":"gemini-3-flash-preview"}}],"options":[]},{"id":"3ceff407-fa73-4a8d-a7c4-32a704c46a64","revisionId":"902a04a9-03d6-4c5b-8d67-0ab4e2d068c8","questionNumber":"2","questionType":"LA","specification":"Ross did an investigation into the relationship between study into temperature ($t$) and total hours of sunshine ($s$) at Heathrow. He finds that the equation of the regression line is $s = 0.25t + 1.3$.","difficulty":1,"totalMarks":1,"sourceTitle":"Question Set 4: Correlation","parts":[{"id":"7443f7ee-e443-4da6-ab6d-0527d70e95b9","label":"0","content":"Give an interpretation of the figure 0.25 figure in this regression line.","markscheme":"- For each additional degree of temperature there is 0.25 additional hours of sunshine B1","marks":1,"order":0,"markingRubric":{"totalMarks":1,"points":[{"id":"p1","marks":1,"description":"Interprets 0.25 as the increase in sunshine hours for every 1 degree increase in temperature.","code":"B"}],"finalAnswers":[],"generatedAt":"2026-05-12T02:14:06.542Z","modelVersion":"gemini-3-flash-preview"}}],"options":[]},{"id":"4e45263a-58ef-43ca-bf38-735e85ae9066","revisionId":"7d7a7246-9495-44e3-bc92-d7fc5f03e794","questionNumber":"3","questionType":"LA","specification":"Tony is investigating the relationship between his daily energy bill in pounds ($e$) and the average daily temperature in degrees ($t$) each day in the winter.\n\nHe finds that the equation of the regression line is $e = 7.3 - 0.4t$","difficulty":1,"totalMarks":3,"sourceTitle":"Question Set 4: Correlation","parts":[{"id":"b94d8af8-d404-4fd1-a8c5-46e097b890f5","label":"a","content":"Describe the correlation between Tony's bill and the average daily temperature.","markscheme":"- As the temperature increases Tony's bill decreases (negative correlation) B1","marks":1,"order":0,"markingRubric":{"totalMarks":1,"points":[{"id":"p1","marks":1,"description":"Identifies negative correlation or describes the inverse relationship.","code":"B"}],"finalAnswers":[],"generatedAt":"2026-05-12T02:14:06.542Z","modelVersion":"gemini-3-flash-preview"}},{"id":"8053be7b-c19e-4c7b-b2fb-daf19eaf35ff","label":"b","content":"Give an interpretation of the gradient of this regression line.","markscheme":"- For each $1^\\circ\\text{C}$ increase in temperature Tony's bill decrease