CCEA GCSE Statistics: how the 200 marks split evenly across two calculator-based papers, the comparative-language and index-number habits that recur in examiner reports, and legal calculator techniques for standard deviation, correlation and binomial questions.
阅读时间 3 分钟更新于: 2026年9月3日
试卷概览
卷数
2
总分
200
考试时间
4小时
题型
12
试卷
时间
分数
题数
比重
题型
Unit 1
2小时
100
10
50%
Outlier detection, stem and leaf diagram, median and range, Sampling bias, survey questions, box plot reading, compound percentage bar chart, Biased coin tree diagram, outcome listing, combined probability and expected frequency, Time series graph interpretation and fixed-base index numbers, Stepped cumulative frequency, data classification, percentiles and deciles, Bivariate scatter diagram, correlation interpretation, line of best fit, Statistical process control chart, target/warning/action lines, out-of-control evaluation, Grouped frequency distribution mean estimate, scaling effects on mean and standard deviation, Quarterly time series, 4-point moving averages, trend line, seasonal forecasting, Normal distribution sketching, standardised z-score, empirical rule probabilities
Unit 2
2小时
100
11
50%
Comparative line graph analysis across demographic groups, Critique of misleading charts and scale misrepresentations, Statistical enquiry cycle planning, hypothesis generation and data sourcing, Continuous cumulative frequency curve, box plot construction, distribution symmetry, Histogram grouped mean estimation and error impact evaluation, Comparative pie charts with area-proportional radius computation, Quarterly time series moving average, trend plotting and extrapolation assumptions, Three-set Venn diagram, conditional probability, cross-group estimation, Chain-base index numbers, missing price computation, geometric mean, Probability tree without replacement and conditional probability deduction, Contingency table relative risk analysis and binomial distribution evaluation
评级
A*ABC*CDEFGU
计算器规定
Both Unit 1 and Unit 2 are calculator papers, and a formula sheet is printed in the exam booklet itself. Calculator statistics functions are expected throughout, including for the mean, standard deviation, and correlation coefficients. The standard JCQ rule applies: no computer algebra or symbolic manipulation function, no communication with another device, and no retrievable information of any kind, including formulae, notes or programs, stored in the calculator. Clear the calculator's memory before the exam or activate its exam mode; the printed formula sheet supplies the formulae, not the calculator's memory.
AO1: Demonstrate knowledge and understanding, using appropriate terminology and notation, of standard statistical techniques used to collect and represent data, and calculate summary statistics and probabilities. (55%)
AO2: Interpret statistical information and results in context and reason statistically to draw conclusions. (25%)
AO3: Assess the appropriateness of statistical methodologies and the conclusions drawn through the application of the statistical enquiry cycle. (20%)
Mean and standard deviation from the statistics mode
Casio fx-83/85 series (scientific)
用途: Get an accurate mean and standard deviation from a frequency table without manual summation errors.
使用时机: Any question giving raw or grouped frequency data and asking for a mean, standard deviation, or the effect of scaling the data.
步骤
Switch the calculator into statistics, one-variable, mode, key in each data value with its frequency using the frequency column, then read the mean and standard deviation directly from the statistics menu rather than summing by hand.
考试提示: This uses the calculator's built-in statistics mode live during the exam with data taken from the question. CCEA and JCQ rules do not allow any formula, note or program to be stored in the calculator beforehand; the printed formula sheet supplies any formulae you need. Activate exam mode if your calculator has one.
Correlation coefficient from the regression mode
Casio fx-83/85 series (scientific)
用途: Get an accurate product moment correlation coefficient directly, as the specification explicitly allows, instead of calculating it term by term.
使用时机: Bivariate scatter diagram questions asking for a correlation coefficient or the equation of a line of best fit.
步骤
Switch the calculator into statistics, two-variable, regression mode, key in each paired x and y value, then read the correlation coefficient and the gradient and intercept of the regression line directly from the statistics menu.
考试提示: This is standard, permitted use of the calculator's regression mode with data entered live from the question during the exam. No dataset, formula or method may be stored in the calculator beforehand.
Cumulative binomial probability in one running total
Casio fx-83/85 series (scientific)
用途: Add several binomial probability terms accurately, such as fewer than three successes, without losing track of which terms have been included.
使用时机: Binomial distribution questions that ask for the probability of fewer than, at most, or at least a given number of successes.
步骤
Calculate each required probability term, for example P(X=0), P(X=1), P(X=2), using the calculator's power and combination, nCr, keys, adding each result into memory with M+ as you go, then use memory recall for the final total.
考试提示: M+ and memory recall are ordinary, permitted arithmetic functions used live during the exam with values calculated from the question. They must not be used to retrieve any binomial table or formula stored before the exam started.
Comparative pie chart radius using the square root key
Casio fx-83/85 series (scientific)
用途: Get the correct new radius for a comparative pie chart, based on area, not on a direct frequency ratio.
使用时机: Comparative pie chart questions that give one radius and frequency and ask for the radius of a second pie chart representing a different frequency.
步骤
Divide the new frequency by the original frequency, multiply by the original radius squared, then take the square root of that result in one continuous calculator entry to get the new radius.
考试提示: This is a live calculation using the calculator's square root and arithmetic keys during the exam. No formula or worked method may be pre-stored in the calculator.
常见错误
1high涉及分数: 1Comparing data sets
Comparing two box plots or two sets of summary statistics is done by stating the isolated numbers, for example a median of 45 against a median of 20, without a comparative sentence explaining what that means.
如何避免: Write the comparison in context: visitors to the second group are on average older, because their median is higher. State the direction and the reason, not just the two numbers.
2high涉及分数: 2Control charts and quality assurance
Warning lines and action lines on a quality control chart are confused, or the required response, an immediate re-sample against stopping the process, is given for the wrong threshold.
如何避免: Treat the warning line and the action line as two separate rules with two separate responses: one point beyond the warning line means re-sample immediately, a point beyond the action line, or two consecutive points beyond the warning line, means stop the process.
3high涉及分数: 2Index numbers
Chain-base index numbers are calculated as a percentage change from the original base year rather than from the immediately preceding period.
如何避免: Before calculating, check whether the index is fixed-base or chain-base. A chain-base index always compares to the period directly before it, not to year one of the series.
4medium涉及分数: 2Population pyramids and comparative pie charts
In comparative pie charts, the new radius is calculated as directly proportional to the frequency rather than proportional to the square root of the frequency, since it is the area that must match the frequency.
如何避免: Use the relationship between the two radii squared and the two frequencies, and take the square root at the final step to get the radius, not the frequency ratio itself.
5medium涉及分数: 1Standardised scores
When comparing standardised z-scores between two distributions, candidates ignore the sign or fail to state that the value closer to zero is closer to its own distribution's mean.
如何避免: Compare the two z-scores by their distance from zero, and state explicitly that the smaller distance means that value is closer to the mean, more typical, of its own distribution.
6medium涉及分数: 1Tables, charts and bar charts
Percentages read from a compound percentage bar chart are treated as if they were raw counts, without checking whether the two groups being compared have different base population sizes.
如何避免: Before comparing two percentages across groups, check whether the underlying totals are the same size. If they are not, the same percentage can represent very different raw numbers.
7medium涉及分数: 1Stem and leaf diagrams
Stem and leaf diagrams are drawn without a key, or with the leaves left unordered within each row.
如何避免: Write the key as the first thing you add to a stem and leaf diagram, and order every row of leaves from smallest to largest before moving on.
8medium涉及分数: 1Venn diagrams and tree diagrams
Conditional probability questions from a Venn diagram or tree diagram use the whole sample space as the denominator instead of the correct restricted subset.
如何避免: Identify exactly which group the question is conditioning on, and use only that group's total as the denominator, not the full sample.