Statistical Inference
133 questions across 6 topics. Also examined in CNET, ISS, GATE ST, GATE DA, JAM MS.
Methods of Estimation, Properties of Estimators
- 132UMP tests are unbiasedMSET June 2025Methods of Estimation, Properties of EstimatorsHard
- 134Minimal sufficiency for N(theta,theta)MSET June 2025Methods of Estimation, Properties of EstimatorsHard
- 135MLE at the boundary of a theta-dependent supportMSET June 2025Methods of Estimation, Properties of EstimatorsHard
- 136Rao–Blackwell versus Lehmann–Scheff\'eMSET June 2025Methods of Estimation, Properties of EstimatorsHard
- 137Consistency of mean and median for U(theta-1,theta+1)MSET June 2025Methods of Estimation, Properties of EstimatorsHard
- 139Consistency in the N(mu,mu^2) modelMSET June 2025Methods of Estimation, Properties of EstimatorsHard
- 142Definition of an unbiased testMSET June 2025Methods of Estimation, Properties of EstimatorsHard
- 147Non-estimable linear parametric functionsMSET June 2025Methods of Estimation, Properties of EstimatorsHard
- 132Cramer–Rao bound — Fisher information of a shifted CauchyMSET April 2024Methods of Estimation, Properties of EstimatorsHard
- 134Sufficiency, ancillarity and the Cramer–Rao bound — reading Basu's theorem carefullyMSET April 2024Methods of Estimation, Properties of EstimatorsHard
- 136MVUE for sigma^2 — known mean removes the Bessel correctionMSET April 2024Methods of Estimation, Properties of EstimatorsHard
- 139Consistency — rescaling makes the extremes behaveMSET April 2024Methods of Estimation, Properties of EstimatorsHard
- 142MLE — the invariance propertyMSET April 2024Methods of Estimation, Properties of EstimatorsMedium
- 131MLE of a Bernoulli parameter restricted to [1/3,2/3]MSET March 2023Methods of Estimation, Properties of EstimatorsEasy
- 132Unbiased estimation of p^3 via a falling-factorial momentMSET March 2023Methods of Estimation, Properties of EstimatorsEasy
- 134UMVUE of e^-theta for Poisson data — a binomial thinning argumentMSET March 2023Methods of Estimation, Properties of EstimatorsMedium
- 137UMVUE of theta^2 for a normal mean with known varianceMSET March 2023Methods of Estimation, Properties of EstimatorsEasy
- 138Spotting the irregular family — support depending on the parameterMSET March 2023Methods of Estimation, Properties of EstimatorsHard
- 139A consistent moment-based estimator for the Laplace scaleMSET March 2023Methods of Estimation, Properties of EstimatorsHard
- 147Normality of errors is needed specifically for the F-test's exact null distributionMSET March 2023Methods of Estimation, Properties of EstimatorsHard
- 168BLUE of beta2 from three uncorrelated, homoscedastic linear combinationsMSET March 2023Methods of Estimation, Properties of EstimatorsMedium
- 113MLE of a normal mean under a non-negativity constraintMSET September 2021Methods of Estimation, Properties of EstimatorsHard
- 116Naming the theorem behind finding sufficient statisticsMSET September 2021Methods of Estimation, Properties of EstimatorsMedium
- 117Exponential family — a complete sufficient statistic need not be unbiased for theta itselfMSET September 2021Methods of Estimation, Properties of EstimatorsHard
- 144Bivariate normal conditioning — using the variance bound to rule out two optionsMSET September 2021Methods of Estimation, Properties of EstimatorsMedium
- 147Minimal sufficiency for a symmetric uniform location familyMSET September 2021Methods of Estimation, Properties of EstimatorsMedium
- 149MLE for the symmetric uniform (-theta,theta) familyMSET September 2021Methods of Estimation, Properties of EstimatorsEasy
- 151Consistency for a shifted-uniform location parameter — the maximum converges to the wrong pointMSET September 2021Methods of Estimation, Properties of EstimatorsMedium
- 116The Cramer–Rao bound is a lower bound restricted to unbiased estimatorsMSET December 2020Methods of Estimation, Properties of EstimatorsMedium
- 117The pooled sums and combined sum of squares form a complete sufficient statistic for two normal samples sharing sigma^2MSET December 2020Methods of Estimation, Properties of EstimatorsHard
- 147Minimal sufficiency for a family of uniforms with index-scaled supportMSET December 2020Methods of Estimation, Properties of EstimatorsMedium
- 148The MLE beats the UMVUE in MSE for normal variance estimationMSET December 2020Methods of Estimation, Properties of EstimatorsHard
- 1512bar Xn, not bar Xn itself, is consistent for the uniform upper endpointMSET December 2020Methods of Estimation, Properties of EstimatorsMedium
- 113The MLE on a restricted parameter space is a boundary-projected sample meanMSET June 2019Methods of Estimation, Properties of EstimatorsMedium
- 116The Rao–Blackwell–Lehmann–Scheffe theorem constructs the UMVUEMSET June 2019Methods of Estimation, Properties of EstimatorsEasy
- 117Likelihood decreasing in theta picks the smallest feasible value, X(n)/5MSET June 2019Methods of Estimation, Properties of EstimatorsEasy
- 147The joint density depends on the data only through X1+2X2MSET June 2019Methods of Estimation, Properties of EstimatorsMedium
- 148A ratio of unbiased estimators is not unbiasedMSET June 2019Methods of Estimation, Properties of EstimatorsEasy
- 149For U(theta,theta+1) any point of [X(n)-1,X(1)] is an MLEMSET June 2019Methods of Estimation, Properties of EstimatorsMedium
- 151Sn^2 is unbiased for sigma^2, but Sn is biased for sigmaMSET June 2019Methods of Estimation, Properties of EstimatorsEasy
- 64With mu known the question should ask about sigma^2, and sum(Xi-mu)^2 is not offeredMSET January 2018 Paper IIMethods of Estimation, Properties of EstimatorsEasy
- 65The Poisson log-likelihood sum xiloglambda-nlambda is concaveMSET January 2018 Paper IIMethods of Estimation, Properties of EstimatorsEasy
- 67The UMVUE is uncorrelated with every unbiased estimator of zeroMSET January 2018 Paper IIMethods of Estimation, Properties of EstimatorsHard
- 93Joint Poisson likelihood: 2lambda^2-3lambda-2=0 gives hatlambda=2MSET January 2018 Paper IIIMethods of Estimation, Properties of EstimatorsMedium
- 94With sigma^2 known, X1+4X2 is sufficient — the printed T1=X1-4X2 is not, and is correlated with T2MSET January 2018 Paper IIIMethods of Estimation, Properties of EstimatorsHard
- 95For U(theta,theta^2) the likelihood falls in theta, so take the least feasible value sqrtX(3)MSET January 2018 Paper IIIMethods of Estimation, Properties of EstimatorsMedium
- 96Sufficiency is joint: bar X alone is not sufficient for mu when sigma^2 is unknownMSET January 2018 Paper IIIMethods of Estimation, Properties of EstimatorsEasy
- 97X is Bernoulli(theta) and complete; X has mean zero whatever thetaMSET January 2018 Paper IIIMethods of Estimation, Properties of EstimatorsMedium
- 108Many functions of the data estimate 1-e^-lambda consistentlyMSET January 2018 Paper IIIMethods of Estimation, Properties of EstimatorsEasy
- 141By symmetry E(tfracX1+X22mid T)=bar X, with variance theta(1-theta)/nMSET January 2018 Paper IIIMethods of Estimation, Properties of EstimatorsMedium
- 65Ebar X^2=theta^2+sigma^2/n, so subtract sigma^2/nMSET April 2017 Paper IIMethods of Estimation, Properties of EstimatorsEasy
- 66The geometric MLE 1/(1+bar x) is at most 1/(1+r) when every xige rMSET April 2017 Paper IIMethods of Estimation, Properties of EstimatorsMedium
- 68For the Laplace location family nothing smaller than the ordered sample is sufficientMSET April 2017 Paper IIMethods of Estimation, Properties of EstimatorsMedium
- 94For the shifted exponential, X(1) is complete sufficient and Basu appliesMSET April 2017 Paper IIIMethods of Estimation, Properties of EstimatorsMedium
- 95Given T=t, each Xi is Bin(t,1/n)MSET April 2017 Paper IIIMethods of Estimation, Properties of EstimatorsMedium
- 96T=sumlog(1+Xi)sim Gamma(n,lambda), and E[(n-1)/T]=lambdaMSET April 2017 Paper IIIMethods of Estimation, Properties of EstimatorsMedium
- 97U(theta,2theta): the likelihood falls in theta on [X(n)/2,X(1)]MSET April 2017 Paper IIIMethods of Estimation, Properties of EstimatorsEasy
- 102For a symmetric population the mean and median are both unbiased and consistentMSET April 2017 Paper IIIMethods of Estimation, Properties of EstimatorsEasy
- 104Dropping one or two observations does not spoil consistencyMSET April 2017 Paper IIIMethods of Estimation, Properties of EstimatorsEasy
Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio Tests
- 106Jump points of a distribution functionMSET June 2025Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
- 133Existence of UMP tests: one-sided versus two-sidedMSET June 2025Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
- 143Pearson's chi-square for a fully specified multinomialMSET June 2025Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
- 133Size of a critical region — summing a binomial tailMSET April 2024Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 135Hypothesis testing — the one statement that survives scrutinyMSET April 2024Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
- 141Testing a Bernoulli proportion — the Wald statisticMSET April 2024Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
- 133Size of a test with a critical region unreachable under H0MSET March 2023Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 150A strongly-supported null hypothesis means a large p-valueMSET March 2023Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 115Power and size of a min-based test for a uniform location parameterMSET September 2021Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 150Nested rejection regions across significance levelsMSET September 2021Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
- 115Matching the chi^2 degrees of freedom to the estimated meanMSET December 2020Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
- 118The F-test for equality of variances needs both independence and normalityMSET December 2020Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
- 120The standard one-sample proportion test statisticMSET December 2020Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 121Degrees of freedom for testing homogeneity of r multinomial populationsMSET December 2020Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 150Monotone likelihood ratio in bar X gives the UMP upper-tail Poisson testMSET December 2020Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 115Computing test size directly under the discrete nullMSET June 2019Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 118The chi^2n-1 null distribution for the sample-variance test statistic requires normalityMSET June 2019Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 150A randomised Neyman–Pearson test: reject at x=4 with probability 0.2MSET June 2019Tests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 66One Bernoulli observation: the size-0.05 MP test must randomise at X=1MSET January 2018 Paper IITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 68For a shifted exponential the minimum carries all the information about the locationMSET January 2018 Paper IITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 71K=mu0+z0.05,sigma/sqrt n with sigma=2MSET January 2018 Paper IITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 100For simple hypotheses the NP test is a likelihood-ratio testMSET January 2018 Paper IIITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 101Poisson MLR in T=sum Xi: reject for large totalsMSET January 2018 Paper IIITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 102Small totals favour a smaller exponential mean; 2T/theta0simchi^22nMSET January 2018 Paper IIITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 103Unbiased: rejection probability at most alpha under H0, at least alpha under H1MSET January 2018 Paper IIITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 107Wilks's theorem: -2loglambdaoversetdlongrightarrowchi^21 under H0MSET January 2018 Paper IIITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 64MLR makes the MP test for one theta1theta0 UMP for all of themMSET April 2017 Paper IITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 67Beta(3,1) against uniform: the likelihood ratio 3x^2 increases in xMSET April 2017 Paper IITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 69Small sum Xi^2 is evidence of a small sigmaMSET April 2017 Paper IITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 70alpha=P2(Xge1)=e^-2 and beta=P1(X<1)=1-e^-1MSET April 2017 Paper IITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsEasy
- 98Uniform scale family: a UMP two-sided test exists (misprinted hypotheses)MSET April 2017 Paper IIITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
- 99The UMPU normal test is the symmetric two-sided z testMSET April 2017 Paper IIITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsMedium
- 100LMP Cauchy test: sum Yi has null variance n/8, so the cut-off is sqrtn/8,zalphaMSET April 2017 Paper IIITests of Hypotheses: MP and UMP Tests, Likelihood Ratio TestsHard
Elementary Bayesian Inference
- 146Poisson likelihood with an exponential priorMSET June 2025Elementary Bayesian InferenceHard
- 145Bayesian binomial — Beta posterior from a uniform priorMSET April 2024Elementary Bayesian InferenceEasy
- 146Bayesian Poisson — a Gamma prior and its posterior meanMSET April 2024Elementary Bayesian InferenceHard
- 145A posterior formula that reproduces both point masses of a two-point priorMSET March 2023Elementary Bayesian InferenceHard
- 146Poisson–Gamma posterior predictive is Negative BinomialMSET March 2023Elementary Bayesian InferenceHard
- 145A loss function engineered to make bar X both Bayes and minimaxMSET September 2021Elementary Bayesian InferenceHard
- 146The Beta family is conjugate for Bernoulli — but the printed option has a typoMSET September 2021Elementary Bayesian InferenceHard
- 146The likelihood's truncation collapses the posterior to a bounded uniformMSET December 2020Elementary Bayesian InferenceMedium
- 145Minimax means the smallest worst-case risk: d2MSET June 2019Elementary Bayesian InferenceEasy
- 146The gamma family is the conjugate prior for a Poisson meanMSET June 2019Elementary Bayesian InferenceEasy
- 87Shrinking towards 1 with weight tfrac12 dominates X when Var X=mu^2+1MSET January 2018 Paper IIIElementary Bayesian InferenceMedium
- 88Gamma(2,2) prior plus Poisson data gives a Gamma(6,5) posteriorMSET January 2018 Paper IIIElementary Bayesian InferenceEasy
- 101Binomial minimax estimator (X+sqrt n/2)/(n+sqrt n)MSET April 2017 Paper IIIElementary Bayesian InferenceHard
Confidence Intervals
- 141Asymptotic confidence interval for the exponential meanMSET June 2025Confidence IntervalsHard
- 114Confidence interval from a single exponential observationMSET September 2021Confidence IntervalsEasy
- 119The correct reading of a confidence intervalMSET September 2021Confidence IntervalsHard
- 114Coverage probability of the sample range as a confidence interval, and a printed-interval flagMSET December 2020Confidence IntervalsHard
- 119A pivotal quantity's distribution is fully known and parameter-freeMSET December 2020Confidence IntervalsMedium
- 114Combining a lower and upper confidence limit into a two-sided intervalMSET June 2019Confidence IntervalsEasy
- 119A larger population variance widens the confidence interval proportionallyMSET June 2019Confidence IntervalsEasy
- 63Coverage 2Phi(K)-1 grows with KMSET April 2017 Paper IIConfidence IntervalsEasy
- 71A function of data and parameter with a parameter-free law is a pivotMSET April 2017 Paper IIConfidence IntervalsEasy
Analysis of Discrete Data and Chi-Square Test of Goodness of Fit
- 159When a quadratic form is not chi-squareMSET June 2025Analysis of Discrete Data and Chi-Square Test of Goodness of FitHard
- 143Contingency tables — expected frequency under independenceMSET April 2024Analysis of Discrete Data and Chi-Square Test of Goodness of FitMedium
- 157Quadratic forms in normal vectors — when A collapses to the identityMSET April 2024Analysis of Discrete Data and Chi-Square Test of Goodness of FitHard
- 159A mixed-sign quadratic form is never chi-squareMSET March 2023Analysis of Discrete Data and Chi-Square Test of Goodness of FitEasy
- 121Degrees of freedom for a chi-square goodness-of-fit test with estimated parameters and merged cellsMSET September 2021Analysis of Discrete Data and Chi-Square Test of Goodness of FitEasy
- 156Ratio of independent normals is Cauchy — W is not chi-squareMSET September 2021Analysis of Discrete Data and Chi-Square Test of Goodness of FitHard
- 160Cochran's theorem: rank-sum equal to n plus positive semi-definiteness gives independent chi-squaresMSET December 2020Analysis of Discrete Data and Chi-Square Test of Goodness of FitHard
- 110Squaring a standard normal quantile gives the chi-square quantileMSET June 2019Analysis of Discrete Data and Chi-Square Test of Goodness of FitEasy
- 121Chi-square degrees of freedom: one for the total, one per estimated parameterMSET June 2019Analysis of Discrete Data and Chi-Square Test of Goodness of FitEasy
- 70Checking a claimed distribution is a goodness-of-fit problemMSET January 2018 Paper IIAnalysis of Discrete Data and Chi-Square Test of Goodness of FitEasy
- 72The 2times2 shortcut chi^2=N(ad-bc)^2/(product of margins)MSET January 2018 Paper IIAnalysis of Discrete Data and Chi-Square Test of Goodness of FitEasy
Nonparametric Tests, Rank Correlation, Test for Independence
- 144Non-parametric analogue of the goodness-of-fit testMSET June 2025Nonparametric Tests, Rank Correlation, Test for IndependenceHard
- 144Choosing a test for the median — nonparametric, small sampleMSET April 2024Nonparametric Tests, Rank Correlation, Test for IndependenceHard
- 122A one-sided sign test p-value from a tiny sampleMSET September 2021Nonparametric Tests, Rank Correlation, Test for IndependenceMedium
- 122Reading the Mann–Whitney U statistic off a fully specified combined rankingMSET December 2020Nonparametric Tests, Rank Correlation, Test for IndependenceMedium
- 122Kendall's tau from the concordant count: (C-D)/binom n2MSET June 2019Nonparametric Tests, Rank Correlation, Test for IndependenceEasy
- 153A U-statistic is the Rao–Blackwellisation of any unbiased kernel estimatorMSET June 2019Nonparametric Tests, Rank Correlation, Test for IndependenceMedium
- 73Expected number of runs: 1+2n1n2/(n1+n2) with 20 men and 13 womenMSET January 2018 Paper IINonparametric Tests, Rank Correlation, Test for IndependenceMedium
- 73Smirnov: 4nDn^+2oversetdlongrightarrowchi^22MSET April 2017 Paper IINonparametric Tests, Rank Correlation, Test for IndependenceMedium