Junior Statistician Qualification Examination study materials
Junior Statistician Qualification Examination study resources

Junior Statistician Qualification Examination study plan

Junior Statistician Qualification Examination · Give each week a clear focus.

8 weeks · About 6 hours per week

Week 1

Descriptive Statistics and Data Presentation

  • Compute and interpret mean, median, mode, quartiles, variance, standard deviation, and coefficient of variation for raw and grouped data, and state which measure suits skewed versus symmetric data.

  • Construct and label frequency tables, cumulative frequency curves, histograms, box plots, and stem-and-leaf displays, then read shape, spread, and outliers back off each display.

  • Detect and explain misleading graph practices such as truncated axes, unequal class widths, and 3D pie distortion, and redraw one flawed chart correctly.

  • Produce a one-page descriptive summary of a real dataset you download yourself, reporting at least six summary statistics and two graphs with captions.

Your checkpoint

A one-page descriptive statistics report on a self-sourced dataset containing a frequency table, two labeled graphs, and six interpreted summary statistics.

Week 2

Probability Theory and Distributions

  • Apply the addition and multiplication rules, conditional probability, and Bayes' theorem to solve at least 15 word problems without looking at solutions first.

  • Distinguish discrete from continuous random variables and compute expectation and variance for binomial, Poisson, hypergeometric, uniform, normal, and exponential models.

  • Standardize normal variables with z-scores and compute tail, interval, and inverse-normal probabilities using tables and software, checking both against each other.

  • State the central limit theorem precisely and simulate sampling distributions in software to show the approach to normality as sample size grows.

Your checkpoint

A solved problem set of 20 probability and distribution exercises with worked steps, plus a simulation output demonstrating the central limit theorem at three sample sizes.

Week 3

Statistical Inference and Estimation

  • Derive and compare the method-of-moments and maximum-likelihood estimators for the binomial and exponential parameters, showing the likelihood steps explicitly.

  • Explain unbiasedness, consistency, efficiency, and sufficiency, and evaluate a given estimator against each criterion.

  • Construct confidence intervals for a mean, a proportion, a difference of means, and a variance, and state the assumptions behind each.

  • Determine the sample size needed for a target margin of error in mean and proportion estimation, and interpret what changing confidence level does to that size.

Your checkpoint

A written comparison of two estimators for one parameter, covering bias, variance, and consistency, with confidence intervals computed for a supplied sample.

Week 4

Hypothesis Testing

  • Frame a research question as null and alternative hypotheses, choose the correct test statistic, and state rejection regions for one- and two-tailed tests.

  • Distinguish Type I and Type II errors, define power, and compute power or required sample size for a one-sample mean test.

  • Run one-sample and two-sample t-tests, paired t-tests, and z-tests for proportions by hand and in software, and reconcile the two results.

  • Interpret p-values correctly, including what a p-value does not tell you, and explain the practical difference between statistical and substantive significance.

Your checkpoint

A hypothesis-testing lab report containing four tests on supplied data, each with hypotheses, assumptions checked, test statistic, p-value, decision, and plain-language conclusion.

Week 5

Regression and Correlation

  • Fit simple linear regression by least squares, compute slope, intercept, residuals, and standard errors, and interpret each coefficient in context.

  • Assess model fit with R-squared, residual plots, and a test on the slope, and identify violations such as nonlinearity and nonconstant variance.

  • Compute and interpret Pearson and Spearman correlation coefficients, and explain how correlation differs from causation and from regression slope.

  • Build and interpret a multiple regression with two or three predictors, including partial coefficients and multicollinearity checks.

Your checkpoint

A regression analysis notebook on one dataset with scatter plot, fitted line, residual diagnostics, coefficient table, and a 200-word interpretation of findings and limitations.

Week 6

Experimental Design and Sampling

  • Compare simple random, stratified, cluster, and systematic sampling on cost, bias risk, and precision, and select an appropriate design for three described scenarios.

  • Design a completely randomized experiment and a randomized block design for stated research questions, specifying treatments, blocks, replication, and randomization procedure.

  • Explain the role of randomization, control, and blocking in reducing bias and variance, and identify confounders in a described study.

  • Compute and interpret a one-way analysis of variance, including the F statistic, degrees of freedom, and post-hoc comparison logic.

Your checkpoint

A two-page experimental design proposal for a stated research question covering sampling method, allocation, blocking, sample size rationale, and planned analysis.

Week 7

Nonparametric Methods and Categorical Data

  • Run and interpret chi-square goodness-of-fit and independence tests, verifying expected counts and applying the continuity or exact-test correction when appropriate.

  • Apply the sign test, Wilcoxon signed-rank test, and Mann-Whitney U test, and justify choosing a nonparametric method over its parametric counterpart.

  • Construct and interpret contingency tables with row, column, and total percentages, and compute measures of association for ordinal data.

  • Identify when Fisher's exact test is required instead of a chi-square test and explain the reason.

Your checkpoint

A categorical and nonparametric analysis sheet with three worked examples, each stating why the chosen test is appropriate and what the result means.

Week 8

Time Series and Index Numbers & Statistical Computing and Data Handling

  • Decompose a time series into trend, seasonal, cyclical, and irregular components, and compute a simple moving average and seasonal index from a short series.

  • Compute and interpret Laspeyres and Paasche price indices, and explain chain linking and substitution bias.

  • Clean a messy dataset in software by handling missing values, recoding types, and detecting duplicates, and document every transformation applied.

  • Complete two full-length timed mock exams under exam conditions and review every wrong answer to its underlying concept.

Your checkpoint

A timed mock exam score record with an error log mapping each missed question to a domain, plus a cleaned dataset and index-number worksheet.

Milestones

Week 2: Score at least 80 percent on a self-made 25-question quiz covering descriptive statistics and probability, with all normal-distribution computations verified in software.

Week 4: Complete the hypothesis-testing lab report with all four tests correct, and explain aloud in under five minutes the difference between a p-value and a Type I error rate.

Week 6: Produce the regression notebook and design proposal, and correctly answer five mixed questions drawn from domains 1 through 6 without notes.

Week 8: Achieve at least 70 percent on both timed mock exams and show an error log where every missed item is linked to a domain and a corrective action.