UPSC ISS Subject Wise Syllabus 2027: Complete Syllabus & Exam Pattern
If you are preparing for the UPSC Indian Statistical Service (ISS) Examination, understanding the syllabus should be your first step.
The ISS examination is not limited to one or two areas of statistics. It covers probability, statistical inference, sampling, econometrics, time series, official statistics, applied statistics and several advanced areas. Along with the four Statistics papers, candidates also have to prepare General English and General Studies.
That is why simply collecting study material is not enough. Before starting preparation, you should know what UPSC actually expects you to study, how each paper is structured, and which topics fall under each subject.
In this guide, we have broken down the UPSC ISS Subject Wise Syllabus 2027 paper by paper so that you can use it as a practical preparation roadmap.
UPSC ISS Exam Pattern
Before going through the detailed syllabus, let's understand the overall examination structure.
The written examination consists of six papers carrying a total of 1000 marks. Candidates who are called for the Viva Voce appear for an additional 200 marks.
| Paper | Subject | Marks | Duration |
|---|---|---|---|
| Paper I | General English | 100 | 3 Hours |
| Paper II | General Studies | 100 | 3 Hours |
| Paper III | Statistics-I | 200 | 2 Hours |
| Paper IV | Statistics-II | 200 | 2 Hours |
| Paper V | Statistics-III | 200 | 3 Hours |
| Paper VI | Statistics-IV | 200 | 3 Hours |
| Written Exam | Total | 1000 | — |
| Viva Voce | Interview | 200 | — |
The standard of General English and General Studies is expected to be at the graduate level, while the Statistics papers are set at the level of a Master's degree examination in the relevant discipline. The syllabus also indicates that candidates should be able to connect theory with facts and analyze problems, particularly in Indian Statistics and Economics.
UPSC ISS Subject Wise Syllabus
Let's now look at the syllabus of every paper.
1. UPSC ISS General English Syllabus
Marks: 100
Duration: 3 Hours
General English is common to both the Indian Economic Service and Indian Statistical Service examinations.
The paper is designed to test your ability to understand and use English effectively.
The syllabus includes:
- Essay writing
- Understanding of English
- Effective use of words
- Passage-based questions
- Summary writing
- Precis writing
The paper is not about memorizing complicated grammar rules. Candidates are expected to demonstrate clear understanding and practical use of the language.
2. UPSC ISS General Studies Syllabus
Marks: 100
Duration: 3 Hours
General Studies is also common to both IES and ISS.
The syllabus broadly covers:
Current Affairs and General Knowledge
Candidates are expected to have knowledge of:
- Current events
- General knowledge
- Everyday observations
- Scientific aspects of common developments
- History
- Polity
- Geography
3. UPSC ISS Statistics-I Syllabus
Marks: 200
Duration: 2 Hours
Type: Objective
Questions: 80
Statistics-I is an objective paper. According to the provided syllabus, it contains four broad areas:
A. Probability
This section covers both fundamental and advanced concepts of probability.
Major topics include:
- Classical and axiomatic probability
- Laws of probability
- Conditional probability
- Bayes' theorem
- Discrete and continuous random variables
- Distribution functions
- Standard probability distributions
- Random vectors
- Joint, marginal and conditional distributions
- Functions of random variables
- Modes of convergence
- Mathematical expectation
- Conditional expectation
- Characteristic functions
- Moment generating and probability generating functions
- Borel 0-1 law
- Kolmogorov 0-1 law
- Tchebycheff's inequality
- Kolmogorov's inequality
- Laws of large numbers
- Central limit theorems
The syllabus specifically includes distributions such as Bernoulli, Binomial, Poisson, Normal, Exponential, Gamma, Beta, Cauchy, Lognormal and others.
B. Statistical Methods
This section focuses on the practical and mathematical foundations of statistics.
Important areas include:
- Data collection
- Data compilation
- Data presentation
- Charts and diagrams
- Histograms
- Frequency distributions
- Measures of location
- Measures of dispersion
- Skewness
- Kurtosis
- Bivariate and multivariate data
- Association and contingency
- Curve fitting
- Orthogonal polynomials
- Bivariate normal distribution
- Linear and polynomial regression
- Correlation
- Partial correlation
- Multiple correlation
- Intraclass correlation
- Correlation ratio
- Standard errors
- Large-sample tests
- Sampling distributions
- t, chi-square and F distributions
- Small-sample tests
- Non-parametric tests
- Order statistics
- Asymptotic relative efficiency
The non-parametric portion includes tests such as Sign, Runs, Wilcoxon, Mann-Whitney, Kolmogorov-Smirnov and others.
C. Numerical Analysis
The Numerical Analysis section covers:
- Finite differences
- Difference operators
- Factorial representation
- Interpolation
- Extrapolation
- Newton-Gregory forward interpolation
- Newton-Gregory backward interpolation
- Divided differences
- Lagrange interpolation
- Central difference formulas
- Error terms
- Inverse interpolation
- Numerical integration
- Trapezoidal rule
- Simpson's one-third rule
- Simpson's three-eighth rule
- Weddle's rule
- Summation of series
- Numerical solutions of differential equations
- Euler's method
- Milne's method
- Picard's method
- Runge-Kutta method
D. Computer Application and Data Processing
This section brings basic computing into the Statistics-I paper.
Topics include:
- Computer fundamentals
- CPU and memory
- Input and output units
- Hardware and peripherals
- System and application software
- Number systems
- Operating systems
- Computer packages and utilities
- Programming languages
- Compilers and assemblers
- RAM and ROM
- Computer memory units
- LAN and WAN
- Internet and intranet
- Computer security
- Viruses
- Antivirus
- Firewall
- Spyware
- Malware
Programming basics include:
- Algorithms
- Flowcharts
- Data and information
- Databases
- Programming languages
- Frontend and backend concepts
- Variables
- Control structures
- Arrays
- Functions
- Modules
- Loops
- Conditional statements
- Exceptions
- Debugging
4. UPSC ISS Statistics-II Syllabus
Marks: 200
Duration: 2 Hours
Type: Objective
Questions: 80
Statistics-II consists of three major areas:
- Linear Models
- Statistical Inference and Hypothesis Testing
- Official Statistics
A. Linear Models
- Theory of linear estimation
- Gauss-Markov models
- Estimable functions
- Error and estimation spaces
- Normal equations
- Least square estimators
- Estimation of error variance
- Correlated observations
- Properties of least square estimators
- Generalized inverse of a matrix
- Variance and covariance of estimators
- One-way and two-way classifications
- Fixed, random and mixed effects models
- Analysis of variance
- Multiple comparison procedures
The syllabus specifically mentions Tukey, Scheffe and Student-Newman-Keuls-Duncan procedures.
B. Statistical Inference and Hypothesis Testing
This is one of the major areas of Statistics-II.
Topics include:
- Properties of good estimators
- Maximum likelihood estimation
- Minimum chi-square estimation
- Method of moments
- Least squares estimation
- Optimal properties of MLE
- Minimum variance unbiased estimators
- Minimum variance bound estimators
- Cramer-Rao inequality
- Bhattacharya bounds
- Sufficient statistics
- Factorization theorem
- Complete statistics
- Rao-Blackwell theorem
- Confidence intervals
- Optimum confidence bounds
- Bootstrap
- Jackknife
Hypothesis testing includes:
- Simple and composite hypotheses
- Type I and Type II errors
- Critical regions
- Similar regions
- Power function
- Most powerful tests
- Uniformly most powerful tests
- Neyman-Pearson lemma
- Unbiased tests
- Randomized tests
- Likelihood ratio tests
- Wald's SPRT
- OC and ASN functions
- Decision theory
C. Official Statistics
Official Statistics is an important part of the ISS syllabus because of its connection with real-world statistical systems.
The syllabus covers:
- National and international statistical systems
- Need and uses of official statistics
- Users of official statistics
- Reliability
- Relevance
- Limitations
- Transparency
- Compilation and collection
- Processing and analysis
- Dissemination
- Agencies involved in official statistics
- National Statistical Organization
- NSSO and CSO
- National Statistical Commission
- Legal provisions
- Index numbers
- Sector-wise statistics
- Agriculture statistics
- Health statistics
- Education statistics
- Women and child statistics
- Surveys and censuses
- National Accounts
- Population Census
- Socio-economic indicators
- Gender statistics
The syllabus also covers agencies, publications, data collection mechanisms and the uses of important statistical indicators.
5. UPSC ISS Statistics-III Syllabus
Marks: 200
Duration: 3 Hours
Type: Descriptive
Statistics-III contains three major areas:
- Sampling Techniques
- Econometrics
- Applied Statistics
A. Sampling Techniques
Topics include:
- Population and sample
- Need for sampling
- Census versus sampling
- Sampling and non-sampling errors
- Sample surveys
- Questionnaires
- Sampling designs
- Field investigation
- NSSO methodologies
- Purposive sampling
- Probability sampling
- Simple random sampling
- Sampling with and without replacement
- Estimation of population mean
- Estimation of population proportion
- Standard errors
- Stratified sampling
- Proportional allocation
- Optimum allocation
- Ratio estimation
- Product estimation
- Regression estimation
- Systematic sampling
- Probability proportional to size sampling
- Horvitz-Thompson estimator
- Cluster sampling
- Multistage sampling
- Two-stage sampling
- Double sampling
- Interpenetrating sub-sampling
This section requires both conceptual clarity and problem-solving ability.
B. Econometrics
The syllabus includes:
- Nature of econometrics
- General Linear Model
- Ordinary Least Squares
- Prediction
- Generalized Least Squares
- Heteroscedasticity
- Pure and mixed estimation
- Autocorrelation
- Tests for autocorrelation
- Theil BLUS procedure
- Multicollinearity
- Ridge regression
- Instrumental variable estimation
- Errors in variables
- Autoregressive regression
- Lagged variables
- Distributed lag models
- Koyck's model
- Simultaneous equation models
- Identification problem
- Structural parameter restrictions
- Rank and order conditions
- Two-stage least squares
- Limited information estimators
- K-class estimators
- Three-stage least squares
- Full information maximum likelihood
- Prediction and simultaneous confidence intervals
C. Applied Statistics
Index Numbers
Topics include:
- Price relatives
- Quantity relatives
- Link relatives
- Chain relatives
- Laspeyres index
- Paasche index
- Marshall-Edgeworth index
- Fisher index
- Chain-base index
- Tests of index numbers
- Wholesale price indices
- Consumer price indices
- Income distribution
- Pareto curves
- Engel curves
- Concentration curves
- National income estimation
- Inter-sectoral flows
- Input-output tables
- Role of CSO
- Demand analysis
Time Series Analysis
This includes:
- Economic time series
- Components of time series
- Additive models
- Multiplicative models
- Trend
- Seasonal fluctuations
- Cyclical fluctuations
- Stochastic processes
- Autocovariance
- Autocorrelation
- Exploratory time series analysis
- Tests for trend and seasonality
- Moving averages
- Exponential smoothing
- Holt and Winters methods
- Forecasting
- MA models
- AR models
- ARMA models
- ARIMA models
- Box-Jenkins models
- Spectral analysis
- Periodogram
- Correlogram
- Fourier transform
6. UPSC ISS Statistics-IV Syllabus
Marks: 200
Duration: 3 Hours
Type: Descriptive
Statistics-IV is slightly different from the other papers.
There are seven sections, and candidates have to choose any two sections. The syllabus states that all sections carry equal marks.
The seven sections are:
- Operations Research and Reliability
- Demography and Vital Statistics
- Survival Analysis and Clinical Trial
- Quality Control
- Multivariate Analysis
- Design and Analysis of Experiments
- Computing with C and R
Let's understand each one.
A. Operations Research and Reliability
This section covers:
- Operations Research fundamentals
- OR models
- Decision-making under uncertainty and risk
- Sensitivity analysis
- Transportation problems
- Assignment problems
- Dynamic programming
- Game theory
- Inventory models
- EOQ
- Queueing models
- M/M/1 and M/M/c models
- M/G/1 queue
- Sequencing and scheduling
- Travelling Salesman Problem
- Replacement problems
- PERT and CPM
- Reliability concepts
- Life distributions
- Hazard rates
- Exponential, Weibull and Gamma distributions
- Reliability estimation
- Aging concepts
- Censored life tests
- Stress-strength reliability
B. Demography and Vital Statistics
This section focuses on population-related statistics.
Important topics include:
- Sources of demographic data
- Census
- Registration systems
- Surveys
- Hospital records
- Indian Census
- Life tables
- National life tables
- UN model life tables
- Abridged life tables
- Stable populations
- Stationary populations
- Fertility measures
- Crude birth rate
- General fertility rate
- Age-specific fertility rate
- Total fertility rate
- Gross reproduction rate
- Net reproduction rate
- Mortality measures
- Crude death rate
- Standardized death rates
- Age-specific death rates
- Infant mortality rate
- Cause-specific mortality
- Internal migration
- International migration
- Migration models
- Population projections
C. Survival Analysis and Clinical Trial
This section combines survival statistics with clinical research.
The syllabus covers:
- Censoring
- Random censoring
- Exponential, Gamma, Weibull and Lognormal distributions
- Pareto distribution
- Failure rate
- Life tables
- Mean residual life
- Survival function
- Actuarial estimator
- Kaplan-Meier estimator
- Tests of exponentiality
- Total time on test
- Gehan test
- Log-rank test
- Cox proportional hazards model
- Competing risk models
Clinical trial topics include:
- Need for clinical trials
- Ethics
- Bias and random error
- Phase I-IV trials
- Multicenter trials
- Data management
- Case report forms
- Database design
- Good Clinical Practice
- Parallel and crossover designs
- Cross-sectional and longitudinal studies
- Factorial designs
- Clinical trial endpoints
- Phase I design
- Phase II design
- Phase III design
- Sequential stopping
- Analysis of categorical outcomes
- Survival data analysis
D. Quality Control
The Quality Control section focuses on statistical process and product control.
Major areas include:
- Quality control concepts
- Process control
- Product control
- Process capability
- Control charts
- Causes of variation
- Control limits
- p chart
- np chart
- c chart
- R chart
- X-bar and R charts
- X-bar and sigma charts
- Process monitoring
- Process optimization
- OC and ARL
- Moving average charts
- EWMA charts
- CUSUM charts
- Economic design of control charts
- Acceptance sampling
- Single sampling plans
- Double sampling plans
- Inspection by variables
E. Multivariate Analysis
This section deals with statistical analysis involving multiple variables.
Topics include:
- Multivariate normal distribution
- Random sampling from multivariate normal populations
- Maximum likelihood estimation
- Sample mean vector
- Wishart distribution
- Generalized variance
- Multiple correlation coefficients
- Hotelling's T²
- Classification problems
- Multivariate classification
- Principal Component Analysis
- Dimension reduction
- Canonical variates
- Canonical correlation
- Estimation and computation
F. Design and Analysis of Experiments
Important topics include:
- One-way classification
- Two-way classification
- Principles of experimental design
- Randomization
- Replication
- Local control
- Completely Randomized Design
- Randomized Block Design
- Latin Square Design
- Missing plot techniques
- Split Plot Design
- Strip Plot Design
- Factorial experiments
- Confounding
- Analysis of covariance
- Non-orthogonal data
- Missing data analysis
G. Computing with C and R
The final section of Statistics-IV focuses on programming and statistical computing.
C Programming
The syllabus includes:
- Components of C
- Structure of a C program
- Data types
- Variables
- Constants
- Operators
- Expressions
- Input and output
- Conditional statements
- Loops
- Arrays
- Storage classes
- Functions
- Parameter passing
- Pointers
- Structures
- Unions
- Linked lists
- File handling
R
Candidates are also expected to know statistical methods and techniques in R.
Which Papers Should You Give More Attention To?
One thing becomes immediately clear from the examination structure: the four Statistics papers account for 800 out of the 1000 written-examination marks.
That means your preparation cannot be built around General Studies and General English alone.
The Statistics papers cover a wide range of topics, from fundamental probability and inference to specialized areas such as survival analysis, multivariate analysis, econometrics, official statistics and statistical computing.
At the same time, Statistics-IV gives you a choice. Since candidates select any two of its seven sections, this choice can become an important part of your preparation strategy.
However, don't select sections simply because they appear familiar. Compare the syllabus with your academic background, available study material and ability to solve descriptive questions.
Objective vs Descriptive Papers in UPSC ISS
The examination pattern makes an important distinction between the Statistics papers.
Statistics-I and Statistics-II are objective papers with 80 questions, 200 marks and 120 minutes.
Statistics-III and Statistics-IV are descriptive papers. Their structure includes short-answer/small-problem questions as well as long-answer/comprehension problems. The syllabus states that candidates have compulsory questions from each section, while Statistics-IV provides a choice of two sections from seven.
This means your preparation should not stop at knowing formulas.
For the objective papers, you need speed and accuracy.
For the descriptive papers, you also need to be able to explain concepts, solve problems step by step and present your answer clearly.
How to Prepare for UPSC ISS Using the Syllabus
A practical way to start ISS preparation is to divide the syllabus into three levels.
Step 1: Build the fundamentals
Step 2: Move towards specialized topics
Step 3: Add computational skills
Do not leave the computer-related portions for the very end.
The syllabus includes computer fundamentals, programming concepts, C programming and statistical methods in R.
Conclusion
The UPSC ISS Subject Wise Syllabus 2027 becomes easier to manage when divided paper-wise. Focus on strong concepts, regular practice and the topics prescribed for each Statistics paper. Keep the syllabus as a checklist throughout your preparation and always verify the final syllabus with the official UPSC notification when released.
Frequently Asked Questions
1. How many papers are there in UPSC ISS?
There are six papers in the written examination: General English, General Studies, Statistics-I, Statistics-II, Statistics-III and Statistics-IV. The written examination carries 1000 marks, followed by a 200-mark Viva Voce for candidates called by the Commission.
2. How many marks are the Statistics papers worth?
There are four Statistics papers, and each carries 200 marks, making the Statistics portion worth 800 marks in total.
3. Which Statistics papers are objective?
Statistics-I and Statistics-II are objective-type papers with 80 questions in each paper and 120 minutes to complete them.
4. Which Statistics papers are descriptive?
Statistics-III and Statistics-IV are descriptive papers with short-answer/small-problem and long-answer/comprehension questions.
5. Is there a choice in Statistics-IV?
Yes. Statistics-IV contains seven sections, and candidates have to choose any two sections. All sections carry equal marks.
6. Is R included in the UPSC ISS syllabus?
Yes. Statistics-IV includes Computing with C and R, including statistical methods and techniques in R.
7. What is the level of the UPSC ISS Statistics papers?
The provided syllabus states that the standard of papers other than General English and General Studies is that of a Master's degree examination in the relevant disciplines.