Econometrics

A Priori
Reasoning from assumptions and logic before looking at data, often used to build economic models.
Ability and Earnings
How differences in skill and other productive traits affect wages, and why that complicates estimates of the return to education.
Acceptance Region
The set of test-statistic values for which a hypothesis test does not reject the null at a chosen significance level.
Adjusted R-Squared
A version of R-squared that penalizes models for adding predictors that do not improve fit enough.
Agent-Based Modelling
A computational approach that simulates many interacting agents and studies the macro patterns that emerge from their behavior.
Aggregate Data
Data created by combining many observations into totals, averages, shares, or rates for a group or economy.
Aitken Estimator
The generalized least squares estimator used when regression errors are correlated or have non-constant variance.
Almon Distributed Lag
A polynomial distributed-lag method that smooths lag coefficients and reduces parameter count in time-series regression.
Almost Sure Convergence
A strong form of probabilistic convergence in which a sequence converges for every outcome except on a set of probability zero.
Analysis of Variance
A statistical method for testing whether group means differ by comparing between-group variation with within-group variation.
Applied Microeconomics
The use of microeconomic theory and data to answer real-world questions about households, firms, and policy.
ARFIMA
An autoregressive fractionally integrated moving average model that captures long memory via fractional differencing.
Asymptotic Distribution
The limiting probability distribution that approximates how a statistic behaves in large samples.
Asymptotic Theory
The study of how estimators and test statistics behave as sample size becomes large.
Augmented Dickey-Fuller Test
A time-series test used to check whether a variable contains a unit root.
Autocorrelation
Correlation between a variable and its own lagged values in a time series.
Autocorrelation Coefficient
The correlation between a time series and a lagged version of itself.
Autocorrelation Function (ACF)
A sequence of correlations between a time series and its own lagged values, used to describe persistence and guide time-series modeling.
Autocovariance
Covariance between a time series and its own lagged values.
Autocovariance Function
The sequence of autocovariances of a stationary time series across different lags.
Automated Econometrics
The use of algorithms to assist with model specification, estimation, testing, and selection in econometric work.
Autoregressive Integrated Moving Average (ARIMA) Model
A time-series forecasting model that combines autoregression, differencing, and moving-average shocks.
Autoregressive Process
A time-series process in which current values depend on past values of the same series.
Bandwidth (Nonparametric Estimation)
The smoothing window that controls how much neighboring data influence a nonparametric estimate.
Bayes Theorem
Bayes theorem is the rule for updating probabilities after observing new evidence.
Bayesian Econometrics
Bayesian econometrics estimates economic models by combining prior beliefs with observed data to form posterior distributions.
Bayesian Inference
Bayesian inference updates probabilities or parameter beliefs by combining prior information with observed data.
Behavioural Equation
A behavioural equation is a structural equation that represents how households, firms, or other agents respond to incentives and constraints.
Best Linear Unbiased Estimator
A best linear unbiased estimator is a linear unbiased estimator with the smallest variance among all linear unbiased estimators.
Best-Fit Line
A best-fit line is the line that summarizes the average linear relationship between two variables in a scatterplot.
Between-Groups Estimator
The between-groups estimator uses group averages in panel data to estimate how outcomes differ across entities rather than within each entity over time.
Bias of an Estimator
The bias of an estimator is the difference between its expected value and the true parameter it is trying to estimate.
Bimodal Distribution
A bimodal distribution has two distinct peaks, often showing that one dataset actually combines two different groups.
Binary Choice Models
Binary choice models estimate the probability of a yes-or-no outcome such as working, defaulting, or buying.
Binomial Distribution
The binomial distribution gives the probability of getting a fixed number of successes in a fixed number of independent trials.
Continuous Distribution
A probability distribution defined over a continuum of values, described by a density function.
Covariance Matrix
A square matrix that collects variances and covariances across multiple variables (used in econometrics and portfolio risk).
Detrending
The process of separating long-run trend movements from short-run fluctuations in economic time series.
Dickey-Fuller
A unit-root test used to assess whether a time series is nonstationary (has a unit root) or mean-reverting.
Discrete Distribution
A probability distribution for variables that take countable values, represented by a probability mass function.
Generalized Method of Moments (GMM) Estimator
An econometric estimator that fits parameters by matching model-implied moments to sample moments.
Goldfeld–Quandt Test
A heteroscedasticity test that compares residual variances across two subsamples ordered by a variable.
Interpolation
Estimating unknown values between observed data points (for example filling missing values within a time series).
Logistic Distribution
A continuous probability distribution with an S-shaped cumulative function, widely used in econometrics.
Omitted Variable Bias
Why regression estimates become biased when a relevant explanatory variable is left out.