Grid Prediction - Prediction Engine

<div class="section-label">02 Grid Prediction</div> <div class="section-title">The primary form of RBP analysis.</div> Evaluates combinations of predictive attributes across relevance and similarity thresholds, then forms a fit-weighted composite prediction for circumstances theta. Combinations that fit this task more reliably pull harder on the forecast. The result also includes variable-level **Impact on Fit** and **Impact on Prediction**. Recommended default path for analysis. Takes the same inputs as the other prediction calls: outcomes y, attributes X, and circumstances theta. ## Signature ```text predict_grid( y, # outcomes, length N X, # attributes, N × K theta, # circumstances, length K options? # GridOptions; omit → defaults ) → results ``` **Call:** `predict_grid` **Options:** `GridOptions` (PredictOptions base + Grid-specific options) **Returns:** [[Results/Overview|Results]] (composite; typically T = 1) ## Arguments | Name | Shape | Description | | --- | --- | --- | | y | N | Observed outcomes | | X | N × K | Training attributes aligned with y | | theta | K | Circumstances for the prediction task | | options | (object) | GridOptions; optional, omit for defaults | N = number of observations (rows), K = number of independent variables (columns). ## Options A grid prediction call is ready with defaults: threshold [0, 0.2, 0.5, 0.8] and censor_type both. Pass a [[Settings/Grid Options#GridOptions|GridOptions]] object when you want to change those. Size policy, sampling, retain keys, and inherited fields: [[Settings/Grid Options|Grid options]]. Allowed value names: [[Settings/Allowed Values|Allowed values]]. When X has holes, **Impact on Fit** and **Impact on Prediction** for incomplete columns are measured against an uninformative version of that column by default. Turn that off with adjust_impact_for_missing. See [[Results/Grid Insights|Grid Insights]]. | Name | Default | Role | | --- | --- | --- | | max_iter | 1000 | Cap on combinations evaluated | | min_k / max_k | 1 / omit | Band of combination sizes. k is the same as min_k | | allowed_k | omit | Exact sizes, such as [1, 3, 7, 10]. Replaces the band | | seed | 42 | RNG seed for sampling and missing-column noise | | attribute_combi | generated | Fixed combination matrix. Omit to sample | | required_attributes | omit | Attributes on in every combination | | attribute_groups | omit | Attributes selected together | | adjust_impact_for_missing | on | Incomplete-column Impact vs uninformative noise | | retain_grid_objects | omit (lean) | Which per-cell objects to keep | | inner_parallel | auto | Parallel over combinations | ## Results A successful Grid call gives you one composite forecast for this task, with fit alongside it, and variable-level **Impact on Fit** and **Impact on Prediction**. Those insights come with the usual result; you do not need to keep per-cell tables to see them. | You get | Look here | | --- | --- | | Forecast and fit | yhat, fit, adjusted_fit, … See [[Results/Core\|Core]] | | Variable impact | **Impact on Fit**, **Impact on Prediction**. See [[Results/Grid Insights\|Grid Insights]] | | Solo distribution / composite ξ | When you retain ysolo_distribution. See [[Results/Solo Distribution\|Solo Distribution]] | | Cell-level tables | When you set retain_grid_objects. See [[Results/Grid Cells\|Grid Cells]] | The full layout of a result object: [[Results/Overview|Results]]. ## Related - [[Functions/Overview|Functions]] - [[Functions/PSR]] · [[MaxFit]] - [[Settings/Grid Options|Grid options]] · [[Results/Overview|Results]] - [[Further reading/01 Overview|Apply RBP to an experiment]]