Time Series Econometrics: open lecture notes

Time Series Econometrics

Open lecture notes. Seventeen lectures that take a single observed path of an economic series and ask what can honestly be learned from it: when averages converge, how to measure the uncertainty of dependent data, how to choose and judge forecasting models, how to test for unit roots, regimes and breaks, and how to model volatility and risk.

In 2016 I attended Stanislav Anatolyev's graduate course in time series econometrics and took my notes by hand on a tablet. These pages are those notes, reworked into slides. The structure and the choice of results follow his lectures; the slides, the examples, the code and any errors are mine. Lecture 8, and a few individual slides elsewhere, cover material that is missing from my notes; they are written from the standard texts and marked as such on the slide.

Each deck opens with a short film that gives the idea before the formalism; it is narrated by a synthetic copy of my voice. The slides are interactive: sliders redraw the figures, the quiz questions check themselves, and every number comes from R code that runs on real data from FRED, shipped with the deck. Open a deck in a browser; the arrow keys move between slides, and F gives full screen.

Foundations

 LectureWhat it coversMaterials
1Stationarity, Ergodicity and White NoiseWhy one trajectory can stand in for many: strict stationarity, three strengths of white noise, ergodicity, and the law of large numbers that needs both.
2Ergodic Theorem, CLT and the Long-Run VarianceAverages of dependent data: the ergodic theorem, the CLT for martingale differences and in general, the long-run variance, and why the naive estimator fails while Newey–West works.
3Time-Series Regression and HAC InferenceOLS on time series: when White standard errors suffice, when HAC is needed, Mishkin's inflation regressions with overlapping horizons; structural versus non-structural models.

Choosing and judging models

 LectureWhat it coversMaterials
4What to Model, and How to Choose a ModelThe objects of modelling — conditional mean, variance, quantiles, density — and the tools for choosing a model: diagnostics, general-to-specific testing, AIC, BIC and Hannan–Quinn.
5In-Sample Fit, Out-of-Sample Forecasts, Diebold–MarianoIn-sample fit against out-of-sample forecasting, fixed, rolling and recursive schemes, and the Diebold–Mariano test of equal predictive ability.
6Data Snooping, Superior Predictive Ability, Model Confidence SetsSearching over many models: data snooping, White's Reality Check, Hansen's SPA test and the model confidence set.

Linear models for the mean

 LectureWhat it coversMaterials
7Linear Projection, Innovations and the Wold DecompositionLinear projection on the infinite past, innovations, the Wold decomposition, impulse responses, and invertibility of moving averages.
8ARMA Models: Identification, Estimation, ForecastingARMA models: roots, ACF and PACF, estimation by least squares and likelihood, the Box–Jenkins cycle, and h-step forecasts with their uncertainty.
9Trends, Unit Roots and Brownian MotionDeterministic and stochastic trends, OLS rates of convergence, the unit-root limit, Brownian motion and the functional CLT.
10Dickey–Fuller, Phillips–Perron and ADF TestsTesting for a unit root: the Dickey–Fuller distributions, deterministic terms, Phillips–Perron and augmented Dickey–Fuller, and why power is low near one.

Nonlinear models for the mean

 LectureWhat it coversMaterials
11Nonlinear Models and Threshold AutoregressionWhy nonlinear models; bilinear and threshold autoregressions, regimes, stationarity with an explosive regime, and estimation by concentrated least squares.
12Threshold Inference and Smooth TransitionInference on the threshold: Hansen's likelihood-ratio confidence set, testing linearity with sup-F and the fixed-regressor bootstrap, and smooth transition (LSTAR, ESTAR).
13Markov Switching and State-Space ModelsLinearity tests against STAR, Markov-switching autoregressions, the Hamilton filter and maximum likelihood, and state-space models.

Several series at once

 LectureWhat it coversMaterials
14Vector Autoregressions, Impulse Responses and CointegrationVector autoregressions: estimation, impulse responses, variance decompositions, Granger causality, spurious regression and cointegration.

Volatility, stability and risk

 LectureWhat it coversMaterials
15Volatility — ARCH and GARCHConditional variance: ARCH and GARCH, Gaussian quasi-maximum likelihood with robust standard errors, the ARCH-LM test, multivariate GARCH and stochastic volatility.
16Structural Breaks and Parameter StabilityBreaks at known and unknown dates: Chow and sup-Wald tests, Andrews' critical values, Bai–Perron multiple breaks, and CUSUM monitoring.
17Realized Volatility, Durations, Direction and Value-at-RiskMeasuring risk: RiskMetrics, realized volatility, duration models, direction-of-change models, Value-at-Risk and its backtest, and CAViaR.

Reading

  • Hamilton, J. D. (1994). Time Series Analysis. Princeton University Press.
  • Tsay, R. S. (2010). Analysis of Financial Time Series, 3rd ed. Wiley.
  • Franses, P. H. and van Dijk, D. (2000). Non-Linear Time Series Models in Empirical Finance. Cambridge University Press.
  • Anatolyev, S. Syllabus of Applied Time Series Econometrics, New Economic School, for the current reading list and the original papers.