Estimator
An estimator is a rule, procedure, or computational model that uses data or measurements to produce an estimate of an unknown quantity, parameter, prediction, or state.
Machine Learning for Tabular Data: XGBoost, Deep Learning, and AI
A scikit-learn-compatible object that implements model fitting and typically prediction or transformation operations.
- How it is used
- Provides a common fit-based interface for tabular modeling, validation, and interchangeable algorithms.
- How deep it goes
- Defines fitting, learned attributes, prediction, transformation, scoring, and cross-validation use without detailing estimator internals.
- Examples
- Uses LogisticRegression with small feature rows and labels, plus BaggingClassifier configured with DecisionTreeClassifier.
- What you can do after
- Apply it via Scikit-learn by fitting models, predicting or transforming new data, and passing models to cross-validation.
Read how Machine Learning for Tabular Data: XGBoost, Deep Learning, and AI explains estimator →
Causal AI
An estimator is a statistic or rule that produces an estimate of an unknown population quantity.
- How it is used
- Deploys estimators after causal identification to compute estimates for selected estimands from observed data.
- How deep it goes
- Explains the query-estimand-estimator distinction and validation workflow, but defers detailed statistical mechanics to a chosen estimator.
- Examples
- Uses Bostonian mean height, MNIST digit probabilities, and DoWhy linear regression for a backdoor estimand.
- What you can do after
- Apply it via DoWhy by selecting an estimator for an identified estimand and checking estimates against synthetic-data ground truth.
Machine Learning Algorithms in Depth
An estimator is a rule that computes an approximation to an unknown statistical quantity from observed data or samples.
- How it is used
- Uses weighted samples from a proposal distribution to estimate expectations and ratios of normalization constants.
- How deep it goes
- Derives importance-sampling estimators, unbiasedness, variance, and consistency, stopping short of broader estimator theory.
- Examples
- Uses truncated Gaussian samples, density-ratio weights, a sinusoidal function, pseudocode, and numerical integration.
- What you can do after
- Apply importance sampling to estimate expectations from normalized or unnormalized target and proposal distributions.
Read how Machine Learning Algorithms in Depth explains estimator →
Related concepts
- point estimateproduces · A point estimate is a single numerical value used to estimate an unknown quantity or parameter.
- double machine learningused by · Double machine learning is a causal-effect estimation method that uses machine-learning nuisance models with orthogonalized estimation to reduce bias from nuisance-function errors.
- Scikit-Learn pipelinepart of · A scikit-learn pipeline is a composite estimator that sequentially chains named data transformations with a final estimator for fitting and prediction.
- fit methoduses · A fit method is an operation that learns or estimates model parameters, structure, or transformation statistics from supplied data.
- front-door estimandmeasures · A front-door estimand is a causal-effect quantity identified from observational data through a mediator that satisfies the front-door identification conditions.
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