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Scholarship Statistics 93201

Time series, bivariate modelling, inference, experiments, statistical literacy and probability. Real NZ data contexts with graphs, strategy prompts, worked steps and s/o marking.

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TierAllBridgeScholarship

Time series Β· 14

  • Holiday-park guest nights in a North Island townTrend, seasonality and additive-model forecastsBridge
  • Electricity demand in two regionsComparing two time series: trends, seasonal effects, relative size, forecastsBridge
  • Monthly e-bike sales at a bike shopCalculating and interpreting moving averagesBridge
  • Quarterly cafΓ© takingsEstimating a seasonal effect from raw and trend valuesBridge
  • Card spending headlinesRaw vs seasonally adjusted figures in news reportsBridge
  • Comparing quarters across yearsYear-on-year vs quarter-on-quarter changesBridge
  • Monthly new light-vehicle registrationsRate of change from a trend lineBridge
  • Quarterly ice-skating rink visitsSeasonal effect from raw and trend valuesBridge
  • Monthly library issuesForecasting from a trend line and seasonal effectBridge
  • Hut bookings on two Great WalksComparing growth of two series with index numbersBridge
  • Census counts for a growing townEvaluating a claim that growth is acceleratingBridge
  • Quarterly visits to an aquatic centreSeasonally adjusted values and headline changesBridge
  • Monthly online job advertisements in a regionMoving-average lag at a turning pointBridge
  • Quarterly water use in a Hawke's Bay townTrend and seasonal description with a forecastBridge

Bivariate data and modelling Β· 15

  • Sunshine hours and kiwifruit dry matterLinear model: describe, predict, residual, causationBridge
  • Daily reading time and reading scoresEffect of an unusual point on a linear modelBridge
  • Temperature and beach-kiosk chip salesRecognising non-linear relationships when r is near zeroBridge
  • Length and weight of snapperInterpreting slope and intercept realisticallyBridge
  • Residuals for a fitness modelResiduals and slope interpretationBridge
  • Bus frequency and patronageDescribing a scatter plot with r and rΒ²Bridge
  • Tree diameter and agePrediction and interpolationBridge
  • Height and arm spanSlope units and rescalingBridge
  • Distance from school and activityDescribing a negative relationshipBridge
  • Study hours and test marksPredictions and residualsBridge
  • Car stopping distancesResidual patterns reveal curvatureBridge
  • Winning times in a multisport raceExtrapolating a time trendBridge
  • Kahikatea height and trunk diameterResidual plot shows curvatureBridge
  • Predator traps and bird countsEffect of an influential pointBridge
  • Extra LED light and tomato seedlingsRegression on a randomly allocated doseBridge

Statistical inference Β· 15

  • E-scooter versus bus commute timesBootstrap confidence interval for a difference in mediansBridge
  • Hauling kina: sample size and precisionEffect of sample size on bootstrap confidence interval widthBridge
  • Volunteering hoursInterpreting a bootstrap CI for a difference in means that contains 0Bridge
  • Repeated samples of hāngΔ« cooking timesSampling variability of the median and the effect of sample sizeBridge
  • Commute distances at two schoolsInformal inference with the DBM/OVS rule for larger samplesBridge
  • Spotting outliers with the IQR ruleIQR and the outlier ruleBridge
  • Weekly pocket moneyInterpreting a bootstrap CI for a meanBridge
  • Reaction-time dataEffect of an outlier on mean and medianBridge
  • Lunchtime screen-free policyInterpreting a bootstrap CI for a differenceBridge
  • A survey at one schoolSample-to-population claimsBridge
  • Waiting for a GP appointmentInterpreting a bootstrap CI for a difference in mediansBridge
  • Travel times for rural vet call-outsInterpreting a bootstrap confidence interval for a medianBridge
  • A regional student bus-use surveyChoosing between cluster and stratified samplingBridge
  • Pāua lengths at two coastal sitesInformal confidence intervals for medians from box plotsBridge
  • Apple weights from two orchardsBootstrap CI for a difference in means and sample sizeBridge

Experimental design Β· 13

  • Chewing gum and word recallExperimental design and randomisation test interpretationBridge
  • Sports drink and 400 m timesMatched-pairs design, blinding, randomisation test on differencesBridge
  • A new vocabulary methodSpotting confounding in a non-randomised comparison and fixing itBridge
  • A herbal throat spray trialPlacebo, blinding and comparing proportionsBridge
  • Mulch and soil moistureExperimental design basicsBridge
  • Paper planesControlling variables in an experimentBridge
  • Fertiliser on paired plotsMatched-pairs differencesBridge
  • Compost and tomato yieldDesign elements and difference in meansBridge
  • Comparing two milk brandsBlinding in a taste testBridge
  • A lunchtime gardening club and eating vegetablesFrom an observational comparison to a randomised designBridge
  • Sit-stand desks and back discomfortWhen participants cannot be blindedBridge
  • A breakfast club and late arrivalsBefore–after comparison without a controlBridge
  • Beetroot juice and rowing timesCrossover design with washout and period effectsBridge

Statistical literacy Β· 17

  • Sun protection survey of senior studentsMargin of error rules of thumb and confidence intervals for differencesBridge
  • Sampling a school by year levelProportional stratified samplingBridge
  • Survey of cycling to workSampling vs non-sampling error; rule-of-thumb MOE outside 30–70%Bridge
  • Dog-bite injuries in two districtsCounts vs rates in comparing regionsBridge
  • Four ways to survey a townIdentifying sampling methods and their biasesBridge
  • Reading a poll's margin of errorMargins of error for subgroupsBridge
  • Youth turnout in a council electionPercentage points vs percentBridge
  • A radio station pollSelf-selected online pollsBridge
  • A poll on daylight savingReading a margin of errorBridge
  • Support for a new skate parkMargin of error and claimsBridge
  • A sales pictogramMisleading pictogramsBridge
  • A weekday phone surveyIdentifying sampling biasBridge
  • A processed-meat headlineRelative vs absolute risk in a health headlineBridge
  • Two wordings of a cycleway questionQuestion-wording effects in a split-sample pollBridge
  • After-hours clinic visits in two districtsPer-person rates vs totalsBridge
  • A suburb's monthly house salesMean vs median in price reportingBridge
  • Polls on an Auckland congestion chargeChecking a 'support has risen' claim against MOEBridge

Probability Β· 21

  • Norovirus in harvested shellfishConditional probability and relative risk from a two-way tableBridge
  • Biosecurity detector dogsTree diagrams, conditional probability, false positivesBridge
  • Pets and sportTwo-set probabilities and testing independenceBridge
  • Desexing and dog incidentsExpected counts, reversed conditional, relative riskBridge
  • Simulating a two-coin gameComparing a simulation estimate with a theoretical probabilityBridge
  • Lunch choices by year levelRow vs column percentages in a two-way tableBridge
  • Smoke alarms in a house'At least one' probabilities with independent componentsBridge
  • Rain and a late busIndependent events and the addition ruleBridge
  • Drawing raffle balls with and without replacementWith vs without replacementBridge
  • Te reo learners and app useExpected frequencies and a reversed conditionalBridge
  • Rain on a school camp'At least one' over several daysBridge
  • Helmet use by cyclist ageConditional probability from a two-way tableBridge
  • Part-time jobs by year levelConditional probability from a two-way tableBridge
  • Testing bore waterTree diagrams and false positivesBridge
  • A school fair spinnerExpected value of a simple gameBridge
  • Picking a waka ama crew at randomSelection without replacement using combinationsBridge
  • Personal locator beacons on a tramping trackConditional probability from percentages in a reportBridge
  • Library cards and children's daily readingChecking independence in a two-way classificationBridge
  • A basketball final seriesProbability of winning a best-of-n seriesBridge
  • Backup power at a rural health centreReliability of systems in series and parallelBridge
  • Choosing Lotto numbersCombinations and at-least-one over many trialsBridge

Statistical investigation Β· 7

  • School library loansCreating derived variables, planning an investigation, data-quality issuesBridge
  • Canteen survey questionsSurvey question design and summarising responsesBridge
  • Questions about a sports club's dataPosing and improving investigative questionsBridge
  • Parkrun resultsDerived variables and choosing displays by variable typeBridge
  • Measuring seedling heightsSources of variation in an investigationBridge
  • Cleaning region labels in a surveyCleaning categorical data before analysisBridge
  • Population, sampling frame and samplePopulations, sampling frames and coverageBridge

Probability distributions Β· 18

  • Kauri seed germinationBinomial model: conditions, probabilities, mean and standard deviationBridge
  • Lamb birth weightsNormal probabilities, inverse normal, model limitationsBridge
  • Waiting for a frequent busContinuous uniform model: probabilities, mean, independenceBridge
  • Typing errors in a newsletterPoisson probabilities and checking mean = varianceBridge
  • Seed germination in a school gardenBinomial mean, SD and point probability; shapeBridge
  • Heights of Year 13 boysNormal probabilities and intervalsBridge
  • Kiwifruit weightsNormal probability between two valuesBridge
  • Guessing on a multiple-choice quizBinomial point probabilitiesBridge
  • Intercepts per netball quarterChecking a Poisson model with mean and varianceBridge
  • Bus journey timesNormal probabilities and percentilesBridge
  • Online shopping preferencesBinomial probabilitiesBridge
  • KererΕ« sightings on a bush walkPoisson probabilitiesBridge
  • Finding an O-negative blood donorWaiting for the first success (geometric model)Bridge
  • Grading free-range eggsNormal conditional probability above a thresholdBridge
  • Ambulance call-outs at a rural stationCombining Poisson rates across periodsBridge
  • Fitness cut-off for a rugby academySetting a normal cut-off so a given proportion qualifiesBridge
  • Load limit in a gondola cabinDistribution of a sample meanBridge
  • Felt earthquakes in a districtPoisson rates over different intervals and a change in rateBridge