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See the economics move.
Interactive diagrams and explainers for the ideas the papers keep testing. Drag the curves, watch the numbers change, then try the real questions that ask about it.
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Guides and diagrams
Showing 61 of 61
India Economy Atlas
A live dashboard of India's economy: GDP, inflation, jobs, RBI rates, the Union Budget and the external sector. Every number carries its source, its freshness and, where the World Bank has one, an independent check.
Oligopoly and monopolistic competition: Cournot, Stackelberg, Bertrand, kinked demand
Reaction functions, leadership, price competition, the kink, cartels, the Herfindahl index and Chamberlin's long run, with seven labs, worked questions and graded past papers up to the Delhi School.
Consumer theory: preferences, budget, demand and the Slutsky equation
A module in seventeen lessons: preferences, utility and the MRS, the budget, utility maximisation, corners, taxes and subsidies, labour supply and saving, demand, elasticity and Engel curves, the Slutsky equation, revealed preference, duality, compensating variation, the properties of demand, and a lesson of Delhi School problems. With labs, a Workbench, worked questions and graded past papers.
Consumer Workbench: demand, expenditure, Slutsky and CV in one screen
Pick tastes and prices and see Marshallian and Hicksian demand, indirect utility, the expenditure function, elasticities, both decompositions of a price change and the money measures, with the identities checked live.
Inflation, unemployment and the Phillips curve: a module from price indices to the natural rate
A module in twelve lessons: measuring inflation and unemployment, the causes and costs of inflation, the original and expectations-augmented Phillips curves, Okun's law, wage-setting and price-setting, supply shocks, disinflation, the curve in real data, and a lesson of Delhi School problems. With labs, worked questions and graded past papers.
Natural-Rate Workbench: wage-setting, price-setting, NAIRU and the Phillips relation in one screen
Pick one of four wage-setting rules and see the natural rate with its working, the Phillips relation it implies, what moves it and the path of inflation when unemployment is held away from it, with the identities checked live.
MODULE
General equilibrium and welfare economics: the Edgeworth box, welfare theorems and social choice
A module in six lessons: the Edgeworth box and the contract curve, competitive equilibrium and Walras' law, efficiency with production, the two welfare theorems, social welfare and compensation tests, and the Delhi School's exchange economies, with labs to move and graded past papers.
MODULE
Econometrics for economics students, from multiple regression to time series
A module in eighteen lessons, built on data where the truth is known: multiple regression, OLS in matrix form and the Gauss-Markov theorem, t and F tests, R squared, dummies, functional form and specification error, multicollinearity, heteroscedasticity and autocorrelation, endogeneity and instruments, simultaneous equations, panel data, binary outcomes, unit roots, ARMA, VAR and cointegration, then a test atlas that says which test fits which problem and the Delhi School's hardest questions, with graded past papers from every exam.
GUIDE
How to read a regression table: coefficients, t, p, R squared and F, on real data
Six answers in a fixed order, practised on an interactive table of real World Bank data: tap any figure to see where it comes from, or cover one and work it out. Then what a table hides: an outlier, unequal spread, overlapping regressors, and the gap between association and cause.
MODULE
Statistical inference for economics students, from joint distributions to hypothesis tests
A module in thirteen lessons: joint distributions and covariance, sampling and the sampling distribution, the standard error and the central limit theorem, estimators and maximum likelihood, confidence intervals, hypothesis tests and p-values, two-sample tests, chi-square tests, analysis of variance and regression inference, on one running example with labs to move and graded past papers.
MODULE
Basic statistics for economics students, from zero to exam level
A module in ten lessons: types of data, the three averages, the geometric and harmonic means, variance and standard deviation, then shape, correlation, regression and index numbers, with a short add-on on growth rates, on one running example, with graded past papers and the Delhi School’s hard problems.
GUIDE
The Lorenz curve and the Gini coefficient: how to draw, calculate and read them
The six kinds of inequality question, drawing a Lorenz curve from incomes or quintile shares, five ways to calculate the Gini, crossing curves and invariance, India's Gini against other countries, and 26 past-paper questions.
International economics, mapped by the question you are stuck on
Balance of payments, exchange rates, PPP and interest parity, tariffs and quotas, and the theories of trade, each on a page that answers one question, with a map of how the topics connect.
Exchange rates: nominal, real and effective, and which way is up
Quotes, appreciation and depreciation, conversion and cross rates, the real exchange rate and how to derive its shortcut, the effective rate, and what moves a floating rate.
Balance of payments: current, capital and financial accounts
What the accounts record, a double-entry drill, where every exam item belongs, the identity, why a deficit has to be financed, and the saving-investment link.
PPP and interest rate parity, covered and uncovered
The law of one price, absolute and relative PPP, forward markets, covered and uncovered interest parity, with a lab for each and the numeric traps examiners use.
Marshall-Lerner condition, the J-curve and devaluation
The condition derived step by step, a J-curve lab, the price-taker and deficit cases, and the elasticities and absorption approaches compared.
Tariffs and quotas: every case, from autarky to a large country
Autarky, free trade, import bans, small and large countries, tariffs, quotas, voluntary export restraints, tariff-rate quotas, subsidies and effective protection, all on one diagram.
Optimum tariff, the terms-of-trade argument and the Metzler paradox
The optimum tariff derived as a monopsony, a tariff-war lab with its prisoner's dilemma, and the Metzler paradox with its condition derived.
Exchange rate regimes and the impossible trinity
The regime menu, how gold and Bretton Woods gave way to floating, a lab that defends a peg until it breaks, a central bank balance sheet under sterilisation, and the trilemma derived from interest parity.
Customs unions, trade creation and diversion, and optimum currency areas
The six stages of integration, Viner's trade creation and diversion with a lab and derivation, and Mundell's optimum currency area with a recovery lab.
Arguments for protection: infant industry, dumping and tariffs against sales taxes
The nine arguments sorted, the infant industry with the Mill and Bastable tests, dumping as price discrimination, a tariff against a sales tax, and a Cournot duopoly with a tariff.
Derivations: how the main results are arrived at, and what they mean
Each derivation starts from the question, defines every symbol, goes one step at a time with a picture where the idea turns, and ends on what the result means and where the exams ask it. Includes a short guide to reading sigma notation and other symbols.
Covariance: what it is, where the formula comes from, and what it means
From the question 'do two things move together?' to the formula, drawn as signed rectangles on Ashanagar households; the shortcut, the rules for shifting, scaling and adding, independence against zero covariance, and the bound that gives correlation.
The binomial and Poisson distributions, derived
The binomial by counting sequences of independent trials, its mean and variance from indicators, and the Poisson as the limit of the binomial, with a sequence counter, a binomial-to-Poisson lab, and the mean and variance worked out.
The exponential and gamma distributions, derived
The exponential as the wait for the first event of a Poisson process, its mean, variance and median, memorylessness, then the gamma as the wait for the r-th event and as a sum of exponentials, with a memoryless lab and a gamma lab with simulated sums.
The normal distribution, derived
The bell as the shape the binomial settles into, the constant 1 over root 2 pi from squaring the integral and slicing it into rings, the mean and variance of the standard normal, and standardising, with a bell lab, a ring lab and a z-score lab.
The chi-square, t and F distributions, derived
All three built from the standard normal: the chi-square as a sum of squares (a gamma), the n - 1 degrees of freedom, the variance interval, the t as a normal over a chi-square and the F as a ratio of chi-squares, with simulation labs for each.
Moment generating functions, derived
M(t) = E[e^(tX)] derived and explored, the moments read from its derivatives, the functions of the binomial, Poisson, exponential, gamma, chi-square and normal found, sums of independent variables and uniqueness, with a curve-and-tangent lab and a Poisson-sum lab.
The negative binomial, lognormal and Pareto distributions, derived
The negative binomial as the wait for the r-th success, the lognormal as the shape of incomes that compound, with mean above median above mode and a Gini that depends on sigma alone, and the Pareto power-law tail with the share of the top and a Gini of 1/(2 alpha - 1), with three labs and the Ashanagar incomes fitted.
MODULE
Theories of international trade, from mercantilism to Krugman
A module in eight short lessons: mercantilism and absolute advantage, Ricardo, offer curves and the terms of trade, Heckscher–Ohlin and its theorems, the Leontief paradox, growth and trade, and new trade theory, with diagrams to move and graded past papers.
GUIDE
The IS–LM–BP model explained: BP curve, capital mobility and all 16 cases
Starts from what the BP curve is and why its slope depends on capital mobility, then works through fiscal and monetary policy under fixed and floating rates in all 16 cases, with labelled diagrams, cheat sheets, an interactive graph and a quiz.
MODULE
IS–LM to AD–AS, from zero to exam level
A module that builds the short-run macro model one curve at a time: the demand for money, the IS and LM curves, policy, aggregate demand and supply, the Phillips curve, expectations and the open economy, each with interactives and graded past-paper sets.
MODULE
Macroeconomics foundations, from zero to exam level
A module of lessons from "what does GDP measure" to the DSE's harder questions: national income, real and nominal GDP, the classical model and Keynes, the Keynesian cross and multipliers, consumption, investment and money, each with interactives and graded past-paper sets.
MODULE
Economic growth: from Harrod–Domar to endogenous growth, from zero to exam level
A module on growth theory: the facts and the production function, growth accounting, Harrod–Domar, the Solow model, the golden rule, convergence, optimal saving, endogenous growth, the Cambridge tradition and growth in practice, each lesson readable on its own, with real data, interactive diagrams and graded past papers.
MODULE
Economic development: theory, measurement and the Indian economy, from zero to exam level
A module on development economics: the human development index and its family, the demographic transition and the measures of population, dual-economy and migration models, poverty traps and strategy, aid, human capital, labour and informality, land and credit, agriculture, the commons and sustainability, each lesson readable on its own, with real data, interactive tools and graded past papers.
MODULE
Probability, from zero to exam level
A module of lessons that starts at "what is a sample space" and ends at the DSE's hardest questions: counting, the rules, conditional probability, Bayes' theorem, random variables, the discrete and continuous distributions, and a final lesson of hard problems, each with its own interactives and graded past-paper sets.
SCHOOLS OF THOUGHT
Schools of economics
Fifteen schools from mercantilism to behavioural economics on one timeline: what each held, its key economists and works, the macro debate from Keynes to the New Keynesians, and a tool to compare schools on one question.
THEORISTS
Theories and their theorists
147 pairings of theory and economist, with years and notes, filterable by field, and a drill in the match-the-list format.
KEY NUMBERS
India's key numbers, 2026
RBI's rate corridor, CRR and SLR; GDP with nominal and PPP ranks; latest quarter's growth; output vs jobs by sector; Budget 2026–27 deficits, top items and the rupee chart. Every figure dated and sourced.
ECONOMIC ACTS
India's economic acts, in order
Twenty-three acts from the RBI Act 1934 to GST in 2017: what each did, what it replaced, passed vs in-force dates, with a self-test mode and a chronology drill.
INSTITUTIONS
When India's institutions were set up
Banks, DFIs, regulators, markets, planning bodies and international institutions on one timeline, from the BSE in 1875 to the MPC in 2016, with a chronology drill.
POVERTY LINES
India's poverty committees, Alagh to Rangarajan
What each committee anchored the poverty line to, the lines and headcounts it produced, and why 2011–12 has two numbers, with a labelled chart of every method.
GUIDE
Measuring poverty: poverty lines, H, PG, P₂ and the MPI
Six ways to measure poverty on one page, each with its symbol, formula and a plain explanation: absolute and relative poverty lines, the headcount ratio, the poverty gap, the squared poverty gap and the multidimensional poverty index, with a calculator.
COMMITTEES
Banking and tax committees of India
Narasimham I (1991) and II (1998) in depth, Chelliah and Kelkar on tax, and every other committee the papers ask about on one interactive timeline.
FINANCE COMMISSIONS
India's Finance Commissions, 1st to 16th
Article 280, vertical and horizontal devolution and grants, seventy years of tax sharing in one chart, and deep dives on the 15th and 16th FCs.
INCOME VS SUBSTITUTION
Income and substitution effects: Hicks and Slutsky
Ten chapters from the basic idea to the Slutsky equation, with a step-by-step decomposition lab and normal, inferior and Giffen goods on live diagrams.
MATRIX RANK
Rank of a matrix, all three ways
Minors, echelon form and normal form, each worked, plus a lab that replays every step for any matrix you type.
MAXIMA AND MINIMA
Maxima, minima, increasing and decreasing
Every derivative test, when each one fails, closed intervals and the profit and cost questions, on a live graph.
HYPOTHESIS TESTING
Hypothesis testing in one place
The 2×2 of Type I and Type II errors, power and p-values, with a lab that shows the α–β trade-off as areas.
TAYLOR SERIES
Taylor series and the simple trick
The table method, the shortcuts that skip it, and a polynomial that wraps around the curve as you add terms.
GAME THEORY
How to solve a game theory question
Dominant strategies, elimination, Nash by underlining, mixed strategies and backward induction, with a solver for any payoff matrix.
EXTERNALITIES
The four types of externalities
Negative and positive, in production and consumption, on one diagram, with the deadweight loss, Pigouvian taxes and the Coase theorem.
LEMONS
Asymmetric information, every type
Adverse selection with a live lemons market, moral hazard, signalling, screening and the principal–agent problem.
LERNER INDEX
Monopoly power and the Lerner index
The whole topic in ten lines, the inverse elasticity rule and a calculator.
MONOPOLY
Monopoly and the deadweight loss
Drag demand and marginal cost and watch the monopoly price, the transfer from consumers and the deadweight loss redraw.
CONSUMER CHOICE
Consumer choice: budget line and indifference curves
Move a price or income and watch the budget line and indifference curve re-tangent, then split the change into its two effects.
SURPLUS
Elasticity and surplus, worked out
Slide a price along a demand curve and watch point elasticity and consumer surplus update, with the working shown line by line.
IS–LM SHOCKS
IS–LM: fiscal and monetary shocks
Raise government spending or the money supply and watch IS and LM shift, then see exactly how much gets crowded out.
PHILLIPS CURVE
The Phillips curve, short run and long run
Push unemployment below its natural rate, then watch expectations catch up and pull it back, step by step.
SOLOW MODEL
The Solow model and the steady state
Watch capital per worker converge to its steady state, then raise the saving rate and see why more output isn't automatically more consumption.
Your pick
Which diagram do you keep getting wrong?
Tell us the topic and we will build the next one around it.
India's economy, 1947 to now
The plans, the crises and the reforms, one scroll long. Each moment links to the questions that test it.