AQA GCSE STATISTICS 8382/2H HIGHER TIER RATING PAPER 2 Mark scheme Version 1.0 MAY 2023

AQA GCSE STATISTICS 8382/2H HIGHER TIER PAPER 2 Mark scheme Version 1.0 Mark schemes are prepared by the Lead Assessment Writer and considered, together with the relevant questions, by a panel of subject teachers. This mark scheme has been prepared for practice papers and has not, therefore, been through the process of standardising that would take place for live papers. Further copies of this mark scheme are available from Glossary for mark schemes GCSE examinations are marked in such a way as to award positive achievement wherever possible. For GCSE Statistics papers, marks are awarded under various categories. If a student uses a method which is not explicitly covered by the marking instructions the same principles of marking should be applied. Credit should be given to any valid methods. Examiners should seek advice from their senior examiner if in any doubt. Key to mark types M Method marks are awarded for a correct method which could lead to a correct answer. A Accuracy marks are awarded when following on from a correct method. It is not necessary to always see the method. This can be implied. B Marks awarded independent of method. ft Follow through marks. Marks awarded for correct working following a mistake in an earlier step. SC Special case. Marks awarded for a common misinterpretation which has some mathematical worth. M dep A method mark dependent on a previous method mark being awarded. B dep A mark that can only be awarded if a previous independent mark has been awarded. oe Or equivalent. Accept answers that are equivalent. eg accept 0.5 as well as 1 2 [a, b] Accept values between a and b inclusive. [a, b) Accept values a ≤ value < b 3.14 … Accept answers which begin 3.14 eg 3.14, 3.142, 3.1416 Use of brackets It is not necessary to see the bracketed work to award the marks. Examiners should consistently apply the following principles Diagrams Diagrams that have working on them should be treated like normal responses. If a diagram has been written on but the correct response is within the answer space, the work within the answer space should be marked. Working on diagrams that contradicts work within the answer space is not to be considered as choice but as working, and is not, therefore, penalised. Responses which appear to come from incorrect methods Whenever there is doubt as to whether a student has used an incorrect method to obtain an answer, as a general principle, the benefit of doubt must be given to the student. In cases where there is no doubt that the answer has come from incorrect working then the student should be penalised. Questions which ask students to show working Instructions on marking will be given but usually marks are not awarded to students who show no working. Questions which do not ask students to show working As a general principle, a correct response is awarded full marks. Misread or miscopy Students often copy values from a question incorrectly. If the examiner thinks that the student has made a genuine misread, then only the accuracy marks (A or B marks), up to a maximum of 2 marks are penalised. The method marks can still be awarded. Further work Once the correct answer has been seen, further working may be ignored unless it goes on to contradict the correct answer. Choice When a choice of answers and/or methods is given, mark each attempt. If both methods are valid then M marks can be awarded but any incorrect answer or method would result in marks being lost. Work not replaced Erased or crossed out work that is still legible should be marked. Work replaced Erased or crossed out work that has been replaced is not awarded marks. Premature approximation Rounding off too early can lead to inaccuracy in the final answer. This should be penalised by 1 mark unless instructed otherwise. Q Answer Marks Comments 1 All the retailer’s stores B1 Any indication 2 200 B1 Any indication 3 A B1 Any indication 4 Discrete B1 Any indication 5 Numbered and labelled scale extending to at least from 1 to 12 B1 oe Label could be ‘sales’ or ‘rocking horses’ Box correctly drawn with median value marked at 6 B1 If there is no scale allow this mark for a box of width 5.5 squares with the median 3 squares from the UQ Minimum value = 1 B1 Implied from graph or clearly shown elsewhere Minimum and maximum values correctly plotted and whiskers drawn to meet box B1 Q Answer Marks Comments 6 (a) Some people can be sensitive about revealing their exact age B1 oe Additional guidance People don’t have to give their exact age B1 People are more likely to tick a box about their age than write down their exact age B1 Age is a sensitive question B1 There are tick boxes to tick B0 It is easy to analyse/collect B0 x 6 (b) Her question does not include a time frame B1 oe Accept there are no tick boxes Additional guidance She has not said if it’s in a week/month/year etc B1 She has used an open question B1 6 (c) She could have tried it out on a small number of people B1 oe Asked someone to check her questionnaire Additional guidance She could have tested it B1 7 (a) 10 434 B1 Q Answer Marks Comments 7 (b) A correct statement about the increasing trend in earnings in both Northern Ireland and the UK eg (median annual) earnings in both Northern Ireland and the UK have increased year on year B2 oe, eg earnings in both regions have steadily increased (each year) there has been an increasing trend in earnings in both Northern Ireland and the UK B1 for a less detailed statement involving either Northern Ireland or the UK or involving a comparison of just two time points eg earnings in Northern Ireland have increased (year on year) earnings in both the UK and Northern Ireland are higher in 2015 than in 2011 The (percentage) increase in earnings in Northern Ireland has been greater B1 The difference in earnings between the two regions has decreased Q Answer Marks Comments 7 (c) A comment that combines house price with earnings eg House prices are lower in East Midlands but earnings are also lower B1 oe, eg house prices are similar but people earn more in Scotland Michael’s conclusion is incorrect B1 oe, eg house prices are more affordable in Scotland (relative to earnings) Additional guidance Accept calculations for the first B mark, eg 196 000  7.8 or 0.0078 25003 and 198 000  7.151or 0.007151 27687 Q Answer Marks Comments 8 (a) 6 and 12 B1 15 and 18 B1ft Follow through on 18 as their 6 + their 12 32 and 23 B1ft For this mark, all rows and columns must add up consistently 8 (b)(i) 6 80 B1ft oe Follow through from their 6 in table 8 (b)(ii) 15 50 B2ft oe Follow through from their table as their number of girls in rock band 50 B1ft for evidence of correct numerator or correct denominator Q Answer Marks Comments 8 (b)(iii) Ticks ‘no’ and a correct reason eg There are equal numbers of boys and girls in the rock band but there are not equal numbers overall or P(R | B) = 15 but P(R | G) = 15 30 50 or P(R) = 30 which is not equal to 80 P(R | G) B2 oe, eg showing R and G are not independent events by considering eg P(R and G) B1 for a partial reason with either a correct conclusion or no conclusion eg there are not equal numbers of boys and girls in the summer school a greater percentage of boys play in the rock band P(R | B) = 15 30 Rock band and gender are not independent Additional guidance Other correct reasons include: Half of all boys are in the rock band but less than half the girls are The rock band is the most popular choice for boys but it is not for girls (therefore not independent) Half of the rock band is boys but less than half on the summer school are boys 9 (a) (3 × 1) + (2 × 2) + (a × 2) + (b × 2) where a = 3, 4 or 5 and b = 6, 7 or 8 M1 29 A1