GCSE Statistics study plan

Classify 25 data items as qualitative/quantitative, discrete/continuous, primary/secondary with at least 90% accuracy.

Compare random, systematic, stratified and quota sampling, and justify a suitable method for three described survey scenarios.

Design an 8-item questionnaire for a stated aim, rewriting at least four leading, ambiguous or overlapping questions.

Construct frequency tables, grouped frequency tables and two-way tables from raw data and read values from them.

Draw bar charts, frequency polygons, histograms with unequal class widths, cumulative frequency curves and box plots from given data.

Calculate frequency density and read medians and quartiles from cumulative frequency graphs and box plots.

Compute mean, median, mode, range and interquartile range from raw data, and estimate the mean from a grouped frequency table.

Interpret each diagram in context, writing a conclusion that names the measure being used and what it shows.

Calculate and interpret standard deviation for a small data set, and state how it differs from range and interquartile range.

Judge skew from box plots and from comparing mean with median, and describe what the skew means for the data.

Compare two distributions using one average and one measure of spread, writing the comparison in the context of the original problem.

Evaluate the effect of an outlier on the mean, median and range, and justify which average to quote.

Plot scatter diagrams from bivariate data and describe correlation as positive or negative and as strong, moderate or weak.

Draw a line of best fit by eye through the mean point and use it to make a prediction, labelling it interpolation or extrapolation and stating why extrapolation is risky.

Explain why correlation does not imply causation and name a plausible confounding variable for three given variable pairs.

Interpret a given correlation coefficient value in terms of direction and strength, avoiding causal language.

Compute 4-point and 3-point moving averages for a given series and plot them over the original time series graph.

Draw a trend line and use it to estimate a future value, stating the assumption the forecast depends on.

Separate a series into trend, seasonal and random variation and calculate the average seasonal effect for each period.

Interpret a time series graph in context, identifying peaks, troughs and any change in the underlying trend.

List outcomes of combined events using sample space diagrams, Venn diagrams and tree diagrams, and use each diagram to calculate probabilities.

Apply the addition and multiplication rules, including conditional probability read from a two-way table.

Estimate probability from relative frequency and comment on how sample size affects reliability.

Calculate expected frequencies and use them to answer a practical question.

Complete a full past-paper-style mock under timed conditions and mark it against the mark scheme before checking answers with anyone else.

Repair every data-collection and representation error from the mock, rewriting the full solution rather than the final answer.

Speed-drill 20 short questions on sampling method choice, table completion and diagram selection in 25 minutes.

Summarise in one page the command words used in the paper and what each demands.

Complete a second full timed mock and compare the score with mock 1 to confirm improvement.

Repair all remaining summarising-data and probability errors, re-attempting each until correct without notes.

Recite from memory the full formula and method list for averages, spread, moving averages, correlation and probability, checking against notes.

Verify that every entry on the error log has been re-attempted and closed out.