Skip to the content

Useful for UGC NET · ASRB NET · ISS

Welcome

This is the complete study package for Estimation Theory (STS-201) together with Section A of STS-205, Estimation Theory and Multivariate Analysis (Conventional). The Foundation course asked which estimator to use; this course asks a harder question — is there a better one, and how would you know? It answers it three times over: by a lower bound no unbiased estimator can beat, by a construction that turns any unbiased estimator into the best one, and by a decision-theoretic framework in which “best” is stated as a risk to be minimised.

What is assumed, and where to revise it. The syllabus names the pre-requisite exactly, and all of it is on this site already: Each unit opens by naming what it borrows and linking it, then goes past it. Nothing already proved in the Foundation notes is proved a second time.

Course Objectives

  1. To understand the procedures for estimating the parameters of a probability distribution by various methods.
  2. To understand the procedures for examining the properties of estimators — consistency, unbiasedness, efficiency, sufficiency, completeness, the minimum variance bound, CAN and BAN.
  3. To estimate a density function from a sample by a non-parametric approach.
  4. To estimate parameters by resampling techniques.

Course Outcomes

  1. Able to estimate the parameters of a probability distribution by various methods.
  2. Able to examine the properties of an estimator — consistency, unbiasedness, efficiency, sufficiency, completeness, the minimum variance bound, CAN and BAN.
  3. Able to estimate a density function from a sample.
  4. Able to evaluate confidence limits for the parameters of any distribution.

Units in this Course

UNIT 1

UMVU Estimation, Cramér–Rao and Rao–Blackwell

Why a criterion alone does not pick an estimator; Fisher's information and its two equal forms; the Cramér–Rao inequality derived from the Cauchy–Schwarz inequality rather than quoted; when the bound is attainable and Bhattacharya's sharper bounds when it is not; and the Rao–Blackwell theorem, with the variance reduction measured on a worked case.

UNIT 2

Completeness, Lehmann–Scheffé, CAN, BAN and Resampling

Completeness as the uniqueness half of the argument; the Lehmann–Scheffé theorem with the uniform case worked in full; maximum likelihood and its large-sample properties; CAN and BAN estimators, with the sample median's efficiency computed; and bias and standard error by the jackknife and the bootstrap.

UNIT 3

U-Statistics, Interval Estimation and Tolerance Limits

Kernels and U-statistics, with the sample variance exhibited as one; the asymptotic distribution stated and used; confidence intervals by pivots for the normal, exponential, binomial and Poisson; the shortest-length interval and how much it actually saves; distribution-free intervals for quantiles; and tolerance limits.

UNIT 4

Decision Theory, Bayes and Minimax, and Density Estimation

Loss, risk and decision functions; admissibility and why it is a weak requirement; prior and posterior distributions and conjugate families; Bayes and minimax estimators under quadratic loss, including the constant-risk minimax for a proportion; then non-parametric density estimation — Rosenblatt's naive estimator, its bias and variance, and kernel estimators worked by hand.

PRACTICAL

STS-205 Section A — Conventional

All five prescribed Section A practicals, each worked by hand with the full arithmetic shown: jackknife estimates, bootstrap estimates, maximum likelihood by the method of scoring for a Cauchy population, confidence limits for the parameters of a normal population, and large-sample confidence limits for the binomial, Poisson and exponential.

REFERENCE

Official Syllabus

The prescribed unit-wise outline for STS-201 and the Section A practical list for STS-205, as printed, with the objectives, outcomes, the stated pre-requisite and the reading list.

How This Course Connects to the Others

What is built hereWhere it is used
Fisher information and the Cramér–Rao bound Every large-sample standard error — the tests in Inferential Statistics, Unit 3 divide by one; and the scoring method in Practical 3
Sufficiency, completeness and Lehmann–Scheffé The exponential family of Distribution Theory, Unit 2 is what makes the theorem applicable; the same route gives the MLE of the mean vector and covariance matrix in Multivariate Analysis (STS-202)
Maximum likelihood and its large-sample properties Fitting the lifetime distributions in STS-107; the likelihood ratio behind every test of a composite hypothesis
Jackknife and bootstrap A standard error wherever no formula exists — including statistics whose exact distribution is unknown, such as a correlation or a ratio
Interval estimation by pivots, and shortest-length intervals The confidence limits quoted in Inferential Statistics, Unit 1, which are built here from the sampling distributions of Distribution Theory, Unit 3
Loss, risk, Bayes and minimax The decision-theoretic reading of testing; conjugate families, which reappear wherever a prior is chosen for convenience
Kernel density estimation Smoothing a histogram into a density curve — Data Science using Python (STS-208), and any exploratory plot of a continuous variable

Next course in learning order: Testing of Hypotheses Statistical inference