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+# Modeling Method Selection
+
+## CART (Regression Trees)
+
+Enable these with `DFATOOL_DTREE_SKLEARN_CART=1` and `--force-tree`.
+
+### Related Options
+
+* `DFATOOL_PARAM_CATEGORIAL_TO_SCALAR=1` converts categorial parameters (which are not supported by CART) to numeric ones.
+
+## XGB (Gradient-Boosted Forests / eXtreme Gradient boosting)
+
+Enable these with `DFATOOL_USE_XGBOOST=1` and `--force-tree`.
+You should also specify `DFATOOL_XGB_N_ESTIMATORS`, `DFATOOL_XGB_MAX_DEPTH`, and possibly `OMP_NUM_THREADS`.
+
+### Related Options
+
+* `DFATOOL_PARAM_CATEGORIAL_TO_SCALAR=1` converts categorial parameters (which are not supported by XGB) to numeric ones.
+* Anything prefixed with `DFATOOL_XGB_`.
+
+## LMT (Linear Model Trees)
+
+Enable these with `DFATOOL_DTREE_LMT=1` and `--force-tree`.
+They always use a maximum depth of 20.
+
+### Related Options
+
+* `DFATOOL_PARAM_CATEGORIAL_TO_SCALAR=1` converts categorial parameters (which are not supported by LMT) to numeric ones.
+
+## RMT (Regression Model Trees)
+
+This is the default modeling method.
+It first uses a heuristic to determine which parameters are relevant, and then builds a non-binary decision tree with function leaves to predict how those affect the performance attribute.
+Depending on the set of relevant parameters and how well they can be modeled with tree and function structures, it may output a simple function (without tree structure), a tree with static leaves, or a single static value that does not take any parameters into account.
+All of these are valid regression model trees.
+
+### Related Options
+
+* `--force-tree` builds a tree structure even if dfatool's heuristic indicates that no non-integer parameter affects the modeled performance attribute.
+* `DFATOOL_DTREE_IGNORE_IRRELEVANT_PARAMS=0` disables the relevant parameter detection heuristic when building the tree structure. By default, irrelevant parameters cannot end up as decision nodes.
+* `DFATOOL_FIT_LINEAR_ONLY=1` makes RMT behave more like LMT by only considering linear functions in leaf nodes.
+* `DFATOOL_SKIP_CODEPENDENT_CHECK=1`
+* `DFATOOL_REGRESSION_SAFE_FUNCTIONS=1`
+
+##
+
+
+* CART: Regression Trees
+* DECART: Regression Trees with exclusively binary features/parameters
+* XGB: Regression Forests
+* LMT: Linear Model Trees
+* RMT: [Regression Model Trees](https://ess.cs.uos.de/static/papers/Friesel-2022-CPSIoTBench.pdf) with [non-binary nodes](https://ess.cs.uos.de/static/papers/Friesel-2022-CAIN.pdf)
+* Least-Squares Regression