Tree-Specific Explanations
Let $BT$ be a Boosted Tree composed of {$T_1,\ldots, T_n$} regression trees and $x$ be an instance.
- A worst instance extending $t$ given $BT$ is an instance $x’$ such that $t \subseteq t_{x’}$ and: \(x' = \mathit{argmin}_{x'': t \subseteq t_{x''}}(\{w(BT, x'')\})\)
- A best instance extending $t$ given $BT$ is an instance $x’$ such that $t \subseteq t_{x’}$ and: \(x' = \mathit{argmax}_{x'': t \subseteq t_{x''}}(\{w(BT, x'')\})\)
$W(t, BT)$ (resp. $B(t, BT)$) denotes the set of worst (resp. best) instances covered by $t$ given $BT$, and $w_\downarrow(t, BT)$ (resp. $w_\uparrow(t, BT)$) denotes the weight of the worst (resp. best) instance covered by $t$ given $F$.
In the multi-class setting, TS-explanations are defined on page dedicated to the Tree-Specific Explanations for Classification.
For the regression case, TS-explanations can be defined as follows:
Let $BT$ be a Boosted Tree composed of {$T_1,\ldots, T_n$} regression trees and $x$ be an instance such that $BT(x) = r$. Let $I=[a,b]$ be an interval containing $r$.
In order to get explanations that best respond to real problems, we do not explain why $BT(x) = r$ but why $BT(x) \in [a,b]$. Note that explaining why $BT(x) = r$ corresponds to computing the direct reason for $x$.
Conceptually, $t$ is a tree-specific explanation for $x$ given $BT$ and be an interval $I=[a,b]$ if and only if $t$ is a subset of $t_{x}$ such that:
- $w_\downarrow(t, BT) \geq a$
- $w_\uparrow(t, BT) \leq b$
- no proper subset of $t$ satisfies the latter condition.
In general, the notions of tree-specific explanation and of sufficient reason do not coincide. Indeed, a sufficient reason is a prime implicant (covering $x$) of the Boosted Tree $BT$, while a tree-specific explanation is an implicant $t$ (covering $x$). Since there is a simple, linear-time algorithm for computing $w_\downarrow(t, F)$ and $w_\uparrow(t, F)$ and for deriving a worst-case and a best-case instance, the tree-specific explanations for $x$ are much easier to compute than the sufficient reasons and they remain abductive.
More information about tree-specific explanations for the classification task can be found in the paper Computing Abductive Explanations for Boosted Trees. For the regression task, more information can be found in the Computing Abductive Explanations for Boosted Regression Trees paper.
The basic methods (initialize, set_instance, to_features, is_reason, …) of the Explainer module used in the next examples are described in the Explainer Principles page.
The method ExplainerRegressionBT.tree_specific_reason allows to compute such explanations. To use it method, you must first call the method set_interval to define an interval.
PyXAI also provides is_tree_specific_reason to check a reason.
Example from Hand-Crafted Trees
To illustrate the generation of a tree-specific explanation, we take an example from the Computing Abductive Explanations for Boosted Regression Trees paper.
Let us consider a loan application scenario. The goal is to predict the amount of money that can be granted to an applicant described using three attributes ($A = {A_1, A_2, A_3}$).
- $A_1$ is a numerical attribute giving the income per month of the applicant
- $A_2$ is a categorical feature giving its employment status as ”employed”, ”unemployed” or ”self-employed”
- $A_3$ is a Boolean feature set to true if the customer is married, false otherwise.

In this example:
- $A_1$ is represented by the feature identifier $F_1$
- $A_2$ has been one-hot encoded and is represented by feature identifiers $F_2$, $F_3$ and $F_4$, each of these features represents respectively the conditions $A_2 = employed$, $A_2 = unemployed$ and $A_2 = self-employed$
- $A_3$ is represented by the feature identifier $F_5$ and the condition $(A_3 = 1)$ (”the applicant is married”)
We consider the instance $x=(2200, 0, 0, 1, 1)$, corresponding to a person with a salary equal to 2200 per month, self-employed (one-hot encoded) and married. Then, $BT(x) = 1500 + 250 + 250 = 2000$.
A tree-specific explanation for the instance $x = (2200, 0, 0, 1, 1)$ and $I=[1500, 2500]$ can be represented by $t = {A_1{>}2000}$. Indeed, we have $w_\downarrow(t, BT) \geq 1500$ and $w_\uparrow(t, BT) \leq 2500$.
The next figure represents the tree-specific reason $t = {A_1{>}2000}$ in red and the dark red leaves give the weights of $w_\downarrow(t, BT)$ for each regression tree of $BT$. We can see that $w_\downarrow(t, BT) = 1500 - 100 + 250 = 1650 \geq 1500$.

The next figure represents the tree-specific explanation $t = {A_1{>}2000}$ in blue and the dark blue leaves give the weights of $w_\uparrow(t, BT)$ for each regression tree of $BT$. We can observe that $w_\uparrow(t, BT) = 1750 + 250 + 100 = 2100 \leq 2500$.

We now show how to get those tree-specific explanations using PyXAI:
from pyxai import Builder, Explaining, Learning
node1_1 = Builder.DecisionNode(1, operator=Builder.GT, threshold=3000, left=1500, right=1750)
node1_2 = Builder.DecisionNode(1, operator=Builder.GT, threshold=2000, left=1000, right=node1_1)
node1_3 = Builder.DecisionNode(1, operator=Builder.GT, threshold=1000, left=0, right=node1_2)
tree1 = Builder.DecisionTree(5, node1_3)
node2_1 = Builder.DecisionNode(5, operator=Builder.EQ, threshold=1, left=100, right=250)
node2_2 = Builder.DecisionNode(4, operator=Builder.EQ, threshold=1, left=-100, right=node2_1)
node2_3 = Builder.DecisionNode(2, operator=Builder.EQ, threshold=1, left=node2_2, right=250)
tree2 = Builder.DecisionTree(5, node2_3)
node3_1 = Builder.DecisionNode(3, operator=Builder.EQ, threshold=1, left=500, right=250)
node3_2 = Builder.DecisionNode(3, operator=Builder.EQ, threshold=1, left=250, right=100)
node3_3 = Builder.DecisionNode(1, operator=Builder.GT, threshold=2000, left=0, right=node3_1)
node3_4 = Builder.DecisionNode(4, operator=Builder.EQ, threshold=1, left=node3_3, right=node3_2)
tree3 = Builder.DecisionTree(5, node3_4)
BTs = Builder.BoostedTreesRegression([tree1, tree2, tree3])
This example can be found in the second part of the Building Boosted Trees page.
instance = (2200, 0, 0, 1, 1) # 2200$, self employed (one hot encoded), married
print("instance:", instance)
loan_types = {
"numerical": Learning.DEFAULT,
"categorical": {"f{2,3,4}": (1, 2, 3)},
"binary": ["f5"],
}
explainer = Explainer.initialize(BTs, instance, features_type=loan_types)
print("prediction:", explainer.predict(instance))
explainer.set_interval(1500, 2500)
tree_specific = explainer.tree_specific_reason()
print("tree specific:", explainer.to_features(tree_specific))
print("is tree : ", explainer.is_tree_specific_reason(tree_specific))
instance: (2200, 0, 0, 1, 1)
--------- Theory Feature Types -----------
Before the encoding (without one hot encoded features), we have:
Numerical features: 1
Categorical features: 1
Binary features: 1
Number of features: 3
Values of categorical features: {'f2': ['f{2,3,4}', 1, (1, 2, 3)], 'f3': ['f{2,3,4}', 2, (1, 2, 3)], 'f4': ['f{2,3,4}', 3, (1, 2, 3)]}
Number of used features in the model (before the encoding): 3
Number of used features in the model (after the encoding): 5
----------------------------------------------
prediction: 2000
tree specific: ('f1 > 2000',)
is tree : True
Example from a Real Dataset
For this example, we take the Houses-prices dataset (this one here). We create a model using the hold-out approach (by default, the test size is set to 30%) and select a well-classified instance. As this dataset contains strings, we encode the data using PyXAI’s Preprocessor:
from pyxai import Learning
preprocessor = Learning.TabularPreprocessor("../../dataset/houses-prices.csv", target_feature="SalePrice", problem_type="regression")
preprocessor.unset_features(["Id"])
preprocessor.set_categorical_features(features=[
"MSSubClass",
"Street",
"LotShape",
"LandContour",
"LotConfig",
"LandSlope",
"Neighborhood",
"Condition1",
"Condition2",
"BldgType",
"HouseStyle",
"OverallQual",
"OverallCond",
"RoofStyle",
"RoofMatl",
"ExterQual",
"ExterCond",
"Foundation",
"Heating",
"HeatingQC",
"CentralAir",
"PavedDrive",
"SaleCondition"])
preprocessor.set_numerical_features({
"LotArea": None,
"YearBuilt": None,
"YearRemodAdd": None,
"1stFlrSF": None,
"2ndFlrSF": None,
"LowQualFinSF": None,
"GrLivArea": None,
"FullBath": None,
"HalfBath": None,
"BedroomAbvGr": None,
"KitchenAbvGr": None,
"TotRmsAbvGrd": None,
"Fireplaces": None,
"WoodDeckSF": None,
"OpenPorchSF": None,
"EnclosedPorch": None,
"3SsnPorch": None,
"ScreenPorch": None,
"PoolArea": None,
"MiscVal": None,
"MoSold": None,
"YrSold": None
})
preprocessor.process()
dataset_name = "../../dataset/houses-prices.csv".split("/")[-1].split(".")[0]+"-converted"
preprocessor.export(dataset_name, output_directory="../../dataset")
-------------- Information ---------------
Problem type: regression
Instances type: tabular
Labels type: None
Dataset path: None
--------------- Converter ---------------
Feature deleted: Id
One hot encoding new features for MSSubClass: 16
-> The feature Street is boolean! No One Hot Encoding for this features.
-> However, the boolean feature Street contains strings. A ordinal encoding must be performed.
One hot encoding new features for LotShape: 4
One hot encoding new features for LandContour: 4
One hot encoding new features for LotConfig: 5
One hot encoding new features for LandSlope: 3
One hot encoding new features for Neighborhood: 25
One hot encoding new features for Condition1: 9
One hot encoding new features for Condition2: 8
One hot encoding new features for BldgType: 5
One hot encoding new features for HouseStyle: 8
One hot encoding new features for OverallQual: 10
One hot encoding new features for OverallCond: 9
One hot encoding new features for RoofStyle: 6
One hot encoding new features for RoofMatl: 8
One hot encoding new features for ExterQual: 4
One hot encoding new features for ExterCond: 5
One hot encoding new features for Foundation: 6
One hot encoding new features for Heating: 6
One hot encoding new features for HeatingQC: 5
-> The feature CentralAir is boolean! No One Hot Encoding for this features.
-> However, the boolean feature CentralAir contains strings. A ordinal encoding must be performed.
One hot encoding new features for PavedDrive: 3
One hot encoding new features for SaleCondition: 6
Dataset saved: ../../dataset/houses-prices-converted.csv
Types saved: ../../dataset/houses-prices-converted.types
-----------------------------------------------
self.data.insert(index, name, transformed_df[name], True)
self.data.insert(index, name, transformed_df[name], True)
self.data.insert(index, name, transformed_df[name], True)
self.data.insert(index, name, transformed_df[name], True)
self.data.insert(index, name, transformed_df[name], True)
self.data.insert(index, name, transformed_df[name], True)
self.data.insert(index, name, transformed_df[name], True)
self.data.insert(index, name, transformed_df[name], True)
self.data.insert(index, name, transformed_df[name], True)
self.data.insert(index, name, transformed_df[name], True)
Index(['Id', 'MSSubClass', 'LotArea', 'Street', 'LotShape', 'LandContour',
'LotConfig', 'LandSlope', 'Neighborhood', 'Condition1', 'Condition2',
'BldgType', 'HouseStyle', 'OverallQual', 'OverallCond', 'YearBuilt',
'YearRemodAdd', 'RoofStyle', 'RoofMatl', 'ExterQual', 'ExterCond',
'Foundation', 'Heating', 'HeatingQC', 'CentralAir', '1stFlrSF',
'2ndFlrSF', 'LowQualFinSF', 'GrLivArea', 'FullBath', 'HalfBath',
'BedroomAbvGr', 'KitchenAbvGr', 'TotRmsAbvGrd', 'Fireplaces',
'PavedDrive', 'WoodDeckSF', 'OpenPorchSF', 'EnclosedPorch', '3SsnPorch',
'ScreenPorch', 'PoolArea', 'MiscVal', 'MoSold', 'YrSold',
'SaleCondition', 'SalePrice'],
dtype='object')
--------------- Converter ---------------
Feature deleted: Id
One hot encoding new features for MSSubClass: 16
-> The feature Street is boolean! No One Hot Encoding for this features.
-> However, the boolean feature Street contains strings. A ordinal encoding must be performed.
One hot encoding new features for LotShape: 4
One hot encoding new features for LandContour: 4
One hot encoding new features for LotConfig: 5
One hot encoding new features for LandSlope: 3
One hot encoding new features for Neighborhood: 25
One hot encoding new features for Condition1: 9
One hot encoding new features for Condition2: 8
One hot encoding new features for BldgType: 5
One hot encoding new features for HouseStyle: 8
One hot encoding new features for OverallQual: 10
One hot encoding new features for OverallCond: 9
One hot encoding new features for RoofStyle: 6
One hot encoding new features for RoofMatl: 8
One hot encoding new features for ExterQual: 4
One hot encoding new features for ExterCond: 5
One hot encoding new features for Foundation: 6
One hot encoding new features for Heating: 6
One hot encoding new features for HeatingQC: 5
-> The feature CentralAir is boolean! No One Hot Encoding for this features.
-> However, the boolean feature CentralAir contains strings. A ordinal encoding must be performed.
One hot encoding new features for PavedDrive: 3
One hot encoding new features for SaleCondition: 6
Dataset saved: ../../dataset/houses-prices-converted_0.csv
Types saved: ../../dataset/houses-prices-converted_0.types
-----------------------------------------------
Now we produce a model and pick up an instance:
from pyxai import Learning, Explaining
learner = Learning.Xgboost("../../dataset/houses-prices-converted_0.csv", problem_type=Learning.REGRESSION)
model = learner.evaluate(splitting_method=Learning.HOLD_OUT, model_type=Learning.BT)
instance, prediction = learner.get_instances(model, n=1)
-------------- Information ---------------
Problem type: regression
Instances type: tabular
Labels type: continuous-values
Dataset path: ../../dataset/houses-prices-converted_0.csv
nFeatures (nAttributes, with the labels): 179
nInstances (nObservations): 2919
--------------- Model creation, fitting and evaluation ---------------
Splitting method: hold-out
Problem type: regression
Models type: boosted-tree
model_parameters: {}
--------- Evaluation Information ---------
For the evaluation number 0:
Metrics:
mean_squared_error: 2027744102.0068274
root_mean_squared_error: 45030.47969994132
mean_absolute_error: 31183.444598122052
Number of Training instances: 2189
Number of Testing instances: 730
--------------- Explainer ----------------
For the split number 0:
**Boosted Tree Regression model**
nTrees: 100
nVariables: 1077
--------------- Instances ----------------
Number of instances selected: 1
----------------------------------------------
Finally, we display a tree-specific explanation for this instance. Note that we activate the theory created by the PyXAI’s Preprocessor by adding the parameter features_type="../../dataset/houses-prices-converted_0.types" to the initialize method. More information about theories are available on this page.
explainer = Explaining.initialize(model, instance, features_type="../../dataset/houses-prices-converted_0.types")
print("instance:", instance)
print("prediction:", prediction)
def compute_delta(percent):
extremum_range = explainer.extremum_range()
difference = extremum_range[1] - extremum_range[0]
return (percent/100)*difference
delta1 = compute_delta(2.5)
explainer.set_interval(prediction - delta1, prediction + delta1)
print("delta1:", delta1)
tree_specific_reason = explainer.tree_specific_reason()
delta2 = compute_delta(5)
explainer.set_interval(prediction - delta2, prediction + delta2)
print("delta2:", delta2)
tree_specific_reason = explainer.tree_specific_reason()
delta3 = compute_delta(10)
explainer.set_interval(prediction - delta3, prediction + delta3)
print("delta3:", delta3)
tree_specific_reason = explainer.tree_specific_reason()
delta4 = compute_delta(20)
explainer.set_interval(prediction - delta4, prediction + delta4)
print("delta4:", delta4)
tree_specific_reason = explainer.tree_specific_reason()
# explainer.visualisation.gui()
feature_names: ['MSSubClass_20', 'MSSubClass_30', 'MSSubClass_40', 'MSSubClass_45', 'MSSubClass_50', 'MSSubClass_60', 'MSSubClass_70', 'MSSubClass_75', 'MSSubClass_80', 'MSSubClass_85', 'MSSubClass_90', 'MSSubClass_120', 'MSSubClass_150', 'MSSubClass_160', 'MSSubClass_180', 'MSSubClass_190', 'LotArea', 'Street', 'LotShape_IR1', 'LotShape_IR2', 'LotShape_IR3', 'LotShape_Reg', 'LandContour_Bnk', 'LandContour_HLS', 'LandContour_Low', 'LandContour_Lvl', 'LotConfig_Corner', 'LotConfig_CulDSac', 'LotConfig_FR2', 'LotConfig_FR3', 'LotConfig_Inside', 'LandSlope_Gtl', 'LandSlope_Mod', 'LandSlope_Sev', 'Neighborhood_Blmngtn', 'Neighborhood_Blueste', 'Neighborhood_BrDale', 'Neighborhood_BrkSide', 'Neighborhood_ClearCr', 'Neighborhood_CollgCr', 'Neighborhood_Crawfor', 'Neighborhood_Edwards', 'Neighborhood_Gilbert', 'Neighborhood_IDOTRR', 'Neighborhood_MeadowV', 'Neighborhood_Mitchel', 'Neighborhood_NAmes', 'Neighborhood_NPkVill', 'Neighborhood_NWAmes', 'Neighborhood_NoRidge', 'Neighborhood_NridgHt', 'Neighborhood_OldTown', 'Neighborhood_SWISU', 'Neighborhood_Sawyer', 'Neighborhood_SawyerW', 'Neighborhood_Somerst', 'Neighborhood_StoneBr', 'Neighborhood_Timber', 'Neighborhood_Veenker', 'Condition1_Artery', 'Condition1_Feedr', 'Condition1_Norm', 'Condition1_PosA', 'Condition1_PosN', 'Condition1_RRAe', 'Condition1_RRAn', 'Condition1_RRNe', 'Condition1_RRNn', 'Condition2_Artery', 'Condition2_Feedr', 'Condition2_Norm', 'Condition2_PosA', 'Condition2_PosN', 'Condition2_RRAe', 'Condition2_RRAn', 'Condition2_RRNn', 'BldgType_1Fam', 'BldgType_2fmCon', 'BldgType_Duplex', 'BldgType_Twnhs', 'BldgType_TwnhsE', 'HouseStyle_1.5Fin', 'HouseStyle_1.5Unf', 'HouseStyle_1Story', 'HouseStyle_2.5Fin', 'HouseStyle_2.5Unf', 'HouseStyle_2Story', 'HouseStyle_SFoyer', 'HouseStyle_SLvl', 'OverallQual_1', 'OverallQual_2', 'OverallQual_3', 'OverallQual_4', 'OverallQual_5', 'OverallQual_6', 'OverallQual_7', 'OverallQual_8', 'OverallQual_9', 'OverallQual_10', 'OverallCond_1', 'OverallCond_2', 'OverallCond_3', 'OverallCond_4', 'OverallCond_5', 'OverallCond_6', 'OverallCond_7', 'OverallCond_8', 'OverallCond_9', 'YearBuilt', 'YearRemodAdd', 'RoofStyle_Flat', 'RoofStyle_Gable', 'RoofStyle_Gambrel', 'RoofStyle_Hip', 'RoofStyle_Mansard', 'RoofStyle_Shed', 'RoofMatl_ClyTile', 'RoofMatl_CompShg', 'RoofMatl_Membran', 'RoofMatl_Metal', 'RoofMatl_Roll', 'RoofMatl_Tar&Grv', 'RoofMatl_WdShake', 'RoofMatl_WdShngl', 'ExterQual_Ex', 'ExterQual_Fa', 'ExterQual_Gd', 'ExterQual_TA', 'ExterCond_Ex', 'ExterCond_Fa', 'ExterCond_Gd', 'ExterCond_Po', 'ExterCond_TA', 'Foundation_BrkTil', 'Foundation_CBlock', 'Foundation_PConc', 'Foundation_Slab', 'Foundation_Stone', 'Foundation_Wood', 'Heating_Floor', 'Heating_GasA', 'Heating_GasW', 'Heating_Grav', 'Heating_OthW', 'Heating_Wall', 'HeatingQC_Ex', 'HeatingQC_Fa', 'HeatingQC_Gd', 'HeatingQC_Po', 'HeatingQC_TA', 'CentralAir', '1stFlrSF', '2ndFlrSF', 'LowQualFinSF', 'GrLivArea', 'FullBath', 'HalfBath', 'BedroomAbvGr', 'KitchenAbvGr', 'TotRmsAbvGrd', 'Fireplaces', 'PavedDrive_N', 'PavedDrive_P', 'PavedDrive_Y', 'WoodDeckSF', 'OpenPorchSF', 'EnclosedPorch', '3SsnPorch', 'ScreenPorch', 'PoolArea', 'MiscVal', 'MoSold', 'YrSold', 'SaleCondition_Abnorml', 'SaleCondition_AdjLand', 'SaleCondition_Alloca', 'SaleCondition_Family', 'SaleCondition_Normal', 'SaleCondition_Partial']
--------- Theory Feature Types -----------
Before the one-hot encoding of categorical features:
Numerical features: 22
Categorical features: 21
Binary features: 2
Number of features: 45
Characteristics of categorical features: {'MSSubClass_20': ['MSSubClass', 20, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_30': ['MSSubClass', 30, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_40': ['MSSubClass', 40, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_45': ['MSSubClass', 45, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_50': ['MSSubClass', 50, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_60': ['MSSubClass', 60, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_70': ['MSSubClass', 70, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_75': ['MSSubClass', 75, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_80': ['MSSubClass', 80, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_85': ['MSSubClass', 85, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_90': ['MSSubClass', 90, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_120': ['MSSubClass', 120, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_150': ['MSSubClass', 150, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_160': ['MSSubClass', 160, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_180': ['MSSubClass', 180, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'MSSubClass_190': ['MSSubClass', 190, [20, 30, 40, 45, 50, 60, 70, 75, 80, 85, 90, 120, 150, 160, 180, 190]], 'LotShape_IR1': ['LotShape', 'IR1', ['IR1', 'IR2', 'IR3', 'Reg']], 'LotShape_IR2': ['LotShape', 'IR2', ['IR1', 'IR2', 'IR3', 'Reg']], 'LotShape_IR3': ['LotShape', 'IR3', ['IR1', 'IR2', 'IR3', 'Reg']], 'LotShape_Reg': ['LotShape', 'Reg', ['IR1', 'IR2', 'IR3', 'Reg']], 'LandContour_Bnk': ['LandContour', 'Bnk', ['Bnk', 'HLS', 'Low', 'Lvl']], 'LandContour_HLS': ['LandContour', 'HLS', ['Bnk', 'HLS', 'Low', 'Lvl']], 'LandContour_Low': ['LandContour', 'Low', ['Bnk', 'HLS', 'Low', 'Lvl']], 'LandContour_Lvl': ['LandContour', 'Lvl', ['Bnk', 'HLS', 'Low', 'Lvl']], 'LotConfig_Corner': ['LotConfig', 'Corner', ['Corner', 'CulDSac', 'FR2', 'FR3', 'Inside']], 'LotConfig_CulDSac': ['LotConfig', 'CulDSac', ['Corner', 'CulDSac', 'FR2', 'FR3', 'Inside']], 'LotConfig_FR2': ['LotConfig', 'FR2', ['Corner', 'CulDSac', 'FR2', 'FR3', 'Inside']], 'LotConfig_FR3': ['LotConfig', 'FR3', ['Corner', 'CulDSac', 'FR2', 'FR3', 'Inside']], 'LotConfig_Inside': ['LotConfig', 'Inside', ['Corner', 'CulDSac', 'FR2', 'FR3', 'Inside']], 'LandSlope_Gtl': ['LandSlope', 'Gtl', ['Gtl', 'Mod', 'Sev']], 'LandSlope_Mod': ['LandSlope', 'Mod', ['Gtl', 'Mod', 'Sev']], 'LandSlope_Sev': ['LandSlope', 'Sev', ['Gtl', 'Mod', 'Sev']], 'Neighborhood_Blmngtn': ['Neighborhood', 'Blmngtn', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_Blueste': ['Neighborhood', 'Blueste', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_BrDale': ['Neighborhood', 'BrDale', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_BrkSide': ['Neighborhood', 'BrkSide', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_ClearCr': ['Neighborhood', 'ClearCr', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_CollgCr': ['Neighborhood', 'CollgCr', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_Crawfor': ['Neighborhood', 'Crawfor', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_Edwards': ['Neighborhood', 'Edwards', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_Gilbert': ['Neighborhood', 'Gilbert', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_IDOTRR': ['Neighborhood', 'IDOTRR', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_MeadowV': ['Neighborhood', 'MeadowV', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_Mitchel': ['Neighborhood', 'Mitchel', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_NAmes': ['Neighborhood', 'NAmes', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_NPkVill': ['Neighborhood', 'NPkVill', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_NWAmes': ['Neighborhood', 'NWAmes', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_NoRidge': ['Neighborhood', 'NoRidge', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_NridgHt': ['Neighborhood', 'NridgHt', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_OldTown': ['Neighborhood', 'OldTown', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_SWISU': ['Neighborhood', 'SWISU', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_Sawyer': ['Neighborhood', 'Sawyer', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_SawyerW': ['Neighborhood', 'SawyerW', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_Somerst': ['Neighborhood', 'Somerst', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_StoneBr': ['Neighborhood', 'StoneBr', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_Timber': ['Neighborhood', 'Timber', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Neighborhood_Veenker': ['Neighborhood', 'Veenker', ['Blmngtn', 'Blueste', 'BrDale', 'BrkSide', 'ClearCr', 'CollgCr', 'Crawfor', 'Edwards', 'Gilbert', 'IDOTRR', 'MeadowV', 'Mitchel', 'NAmes', 'NPkVill', 'NWAmes', 'NoRidge', 'NridgHt', 'OldTown', 'SWISU', 'Sawyer', 'SawyerW', 'Somerst', 'StoneBr', 'Timber', 'Veenker']], 'Condition1_Artery': ['Condition1', 'Artery', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNe', 'RRNn']], 'Condition1_Feedr': ['Condition1', 'Feedr', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNe', 'RRNn']], 'Condition1_Norm': ['Condition1', 'Norm', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNe', 'RRNn']], 'Condition1_PosA': ['Condition1', 'PosA', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNe', 'RRNn']], 'Condition1_PosN': ['Condition1', 'PosN', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNe', 'RRNn']], 'Condition1_RRAe': ['Condition1', 'RRAe', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNe', 'RRNn']], 'Condition1_RRAn': ['Condition1', 'RRAn', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNe', 'RRNn']], 'Condition1_RRNe': ['Condition1', 'RRNe', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNe', 'RRNn']], 'Condition1_RRNn': ['Condition1', 'RRNn', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNe', 'RRNn']], 'Condition2_Artery': ['Condition2', 'Artery', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNn']], 'Condition2_Feedr': ['Condition2', 'Feedr', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNn']], 'Condition2_Norm': ['Condition2', 'Norm', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNn']], 'Condition2_PosA': ['Condition2', 'PosA', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNn']], 'Condition2_PosN': ['Condition2', 'PosN', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNn']], 'Condition2_RRAe': ['Condition2', 'RRAe', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNn']], 'Condition2_RRAn': ['Condition2', 'RRAn', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNn']], 'Condition2_RRNn': ['Condition2', 'RRNn', ['Artery', 'Feedr', 'Norm', 'PosA', 'PosN', 'RRAe', 'RRAn', 'RRNn']], 'BldgType_1Fam': ['BldgType', '1Fam', ['1Fam', '2fmCon', 'Duplex', 'Twnhs', 'TwnhsE']], 'BldgType_2fmCon': ['BldgType', '2fmCon', ['1Fam', '2fmCon', 'Duplex', 'Twnhs', 'TwnhsE']], 'BldgType_Duplex': ['BldgType', 'Duplex', ['1Fam', '2fmCon', 'Duplex', 'Twnhs', 'TwnhsE']], 'BldgType_Twnhs': ['BldgType', 'Twnhs', ['1Fam', '2fmCon', 'Duplex', 'Twnhs', 'TwnhsE']], 'BldgType_TwnhsE': ['BldgType', 'TwnhsE', ['1Fam', '2fmCon', 'Duplex', 'Twnhs', 'TwnhsE']], 'HouseStyle_1.5Fin': ['HouseStyle', '1.5Fin', ['1.5Fin', '1.5Unf', '1Story', '2.5Fin', '2.5Unf', '2Story', 'SFoyer', 'SLvl']], 'HouseStyle_1.5Unf': ['HouseStyle', '1.5Unf', ['1.5Fin', '1.5Unf', '1Story', '2.5Fin', '2.5Unf', '2Story', 'SFoyer', 'SLvl']], 'HouseStyle_1Story': ['HouseStyle', '1Story', ['1.5Fin', '1.5Unf', '1Story', '2.5Fin', '2.5Unf', '2Story', 'SFoyer', 'SLvl']], 'HouseStyle_2.5Fin': ['HouseStyle', '2.5Fin', ['1.5Fin', '1.5Unf', '1Story', '2.5Fin', '2.5Unf', '2Story', 'SFoyer', 'SLvl']], 'HouseStyle_2.5Unf': ['HouseStyle', '2.5Unf', ['1.5Fin', '1.5Unf', '1Story', '2.5Fin', '2.5Unf', '2Story', 'SFoyer', 'SLvl']], 'HouseStyle_2Story': ['HouseStyle', '2Story', ['1.5Fin', '1.5Unf', '1Story', '2.5Fin', '2.5Unf', '2Story', 'SFoyer', 'SLvl']], 'HouseStyle_SFoyer': ['HouseStyle', 'SFoyer', ['1.5Fin', '1.5Unf', '1Story', '2.5Fin', '2.5Unf', '2Story', 'SFoyer', 'SLvl']], 'HouseStyle_SLvl': ['HouseStyle', 'SLvl', ['1.5Fin', '1.5Unf', '1Story', '2.5Fin', '2.5Unf', '2Story', 'SFoyer', 'SLvl']], 'OverallQual_1': ['OverallQual', 1, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallQual_2': ['OverallQual', 2, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallQual_3': ['OverallQual', 3, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallQual_4': ['OverallQual', 4, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallQual_5': ['OverallQual', 5, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallQual_6': ['OverallQual', 6, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallQual_7': ['OverallQual', 7, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallQual_8': ['OverallQual', 8, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallQual_9': ['OverallQual', 9, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallQual_10': ['OverallQual', 10, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]], 'OverallCond_1': ['OverallCond', 1, [1, 2, 3, 4, 5, 6, 7, 8, 9]], 'OverallCond_2': ['OverallCond', 2, [1, 2, 3, 4, 5, 6, 7, 8, 9]], 'OverallCond_3': ['OverallCond', 3, [1, 2, 3, 4, 5, 6, 7, 8, 9]], 'OverallCond_4': ['OverallCond', 4, [1, 2, 3, 4, 5, 6, 7, 8, 9]], 'OverallCond_5': ['OverallCond', 5, [1, 2, 3, 4, 5, 6, 7, 8, 9]], 'OverallCond_6': ['OverallCond', 6, [1, 2, 3, 4, 5, 6, 7, 8, 9]], 'OverallCond_7': ['OverallCond', 7, [1, 2, 3, 4, 5, 6, 7, 8, 9]], 'OverallCond_8': ['OverallCond', 8, [1, 2, 3, 4, 5, 6, 7, 8, 9]], 'OverallCond_9': ['OverallCond', 9, [1, 2, 3, 4, 5, 6, 7, 8, 9]], 'RoofStyle_Flat': ['RoofStyle', 'Flat', ['Flat', 'Gable', 'Gambrel', 'Hip', 'Mansard', 'Shed']], 'RoofStyle_Gable': ['RoofStyle', 'Gable', ['Flat', 'Gable', 'Gambrel', 'Hip', 'Mansard', 'Shed']], 'RoofStyle_Gambrel': ['RoofStyle', 'Gambrel', ['Flat', 'Gable', 'Gambrel', 'Hip', 'Mansard', 'Shed']], 'RoofStyle_Hip': ['RoofStyle', 'Hip', ['Flat', 'Gable', 'Gambrel', 'Hip', 'Mansard', 'Shed']], 'RoofStyle_Mansard': ['RoofStyle', 'Mansard', ['Flat', 'Gable', 'Gambrel', 'Hip', 'Mansard', 'Shed']], 'RoofStyle_Shed': ['RoofStyle', 'Shed', ['Flat', 'Gable', 'Gambrel', 'Hip', 'Mansard', 'Shed']], 'RoofMatl_ClyTile': ['RoofMatl', 'ClyTile', ['ClyTile', 'CompShg', 'Membran', 'Metal', 'Roll', 'Tar&Grv', 'WdShake', 'WdShngl']], 'RoofMatl_CompShg': ['RoofMatl', 'CompShg', ['ClyTile', 'CompShg', 'Membran', 'Metal', 'Roll', 'Tar&Grv', 'WdShake', 'WdShngl']], 'RoofMatl_Membran': ['RoofMatl', 'Membran', ['ClyTile', 'CompShg', 'Membran', 'Metal', 'Roll', 'Tar&Grv', 'WdShake', 'WdShngl']], 'RoofMatl_Metal': ['RoofMatl', 'Metal', ['ClyTile', 'CompShg', 'Membran', 'Metal', 'Roll', 'Tar&Grv', 'WdShake', 'WdShngl']], 'RoofMatl_Roll': ['RoofMatl', 'Roll', ['ClyTile', 'CompShg', 'Membran', 'Metal', 'Roll', 'Tar&Grv', 'WdShake', 'WdShngl']], 'RoofMatl_Tar&Grv': ['RoofMatl', 'Tar&Grv', ['ClyTile', 'CompShg', 'Membran', 'Metal', 'Roll', 'Tar&Grv', 'WdShake', 'WdShngl']], 'RoofMatl_WdShake': ['RoofMatl', 'WdShake', ['ClyTile', 'CompShg', 'Membran', 'Metal', 'Roll', 'Tar&Grv', 'WdShake', 'WdShngl']], 'RoofMatl_WdShngl': ['RoofMatl', 'WdShngl', ['ClyTile', 'CompShg', 'Membran', 'Metal', 'Roll', 'Tar&Grv', 'WdShake', 'WdShngl']], 'ExterQual_Ex': ['ExterQual', 'Ex', ['Ex', 'Fa', 'Gd', 'TA']], 'ExterQual_Fa': ['ExterQual', 'Fa', ['Ex', 'Fa', 'Gd', 'TA']], 'ExterQual_Gd': ['ExterQual', 'Gd', ['Ex', 'Fa', 'Gd', 'TA']], 'ExterQual_TA': ['ExterQual', 'TA', ['Ex', 'Fa', 'Gd', 'TA']], 'ExterCond_Ex': ['ExterCond', 'Ex', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'ExterCond_Fa': ['ExterCond', 'Fa', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'ExterCond_Gd': ['ExterCond', 'Gd', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'ExterCond_Po': ['ExterCond', 'Po', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'ExterCond_TA': ['ExterCond', 'TA', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'Foundation_BrkTil': ['Foundation', 'BrkTil', ['BrkTil', 'CBlock', 'PConc', 'Slab', 'Stone', 'Wood']], 'Foundation_CBlock': ['Foundation', 'CBlock', ['BrkTil', 'CBlock', 'PConc', 'Slab', 'Stone', 'Wood']], 'Foundation_PConc': ['Foundation', 'PConc', ['BrkTil', 'CBlock', 'PConc', 'Slab', 'Stone', 'Wood']], 'Foundation_Slab': ['Foundation', 'Slab', ['BrkTil', 'CBlock', 'PConc', 'Slab', 'Stone', 'Wood']], 'Foundation_Stone': ['Foundation', 'Stone', ['BrkTil', 'CBlock', 'PConc', 'Slab', 'Stone', 'Wood']], 'Foundation_Wood': ['Foundation', 'Wood', ['BrkTil', 'CBlock', 'PConc', 'Slab', 'Stone', 'Wood']], 'Heating_Floor': ['Heating', 'Floor', ['Floor', 'GasA', 'GasW', 'Grav', 'OthW', 'Wall']], 'Heating_GasA': ['Heating', 'GasA', ['Floor', 'GasA', 'GasW', 'Grav', 'OthW', 'Wall']], 'Heating_GasW': ['Heating', 'GasW', ['Floor', 'GasA', 'GasW', 'Grav', 'OthW', 'Wall']], 'Heating_Grav': ['Heating', 'Grav', ['Floor', 'GasA', 'GasW', 'Grav', 'OthW', 'Wall']], 'Heating_OthW': ['Heating', 'OthW', ['Floor', 'GasA', 'GasW', 'Grav', 'OthW', 'Wall']], 'Heating_Wall': ['Heating', 'Wall', ['Floor', 'GasA', 'GasW', 'Grav', 'OthW', 'Wall']], 'HeatingQC_Ex': ['HeatingQC', 'Ex', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'HeatingQC_Fa': ['HeatingQC', 'Fa', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'HeatingQC_Gd': ['HeatingQC', 'Gd', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'HeatingQC_Po': ['HeatingQC', 'Po', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'HeatingQC_TA': ['HeatingQC', 'TA', ['Ex', 'Fa', 'Gd', 'Po', 'TA']], 'PavedDrive_N': ['PavedDrive', 'N', ['N', 'P', 'Y']], 'PavedDrive_P': ['PavedDrive', 'P', ['N', 'P', 'Y']], 'PavedDrive_Y': ['PavedDrive', 'Y', ['N', 'P', 'Y']], 'SaleCondition_Abnorml': ['SaleCondition', 'Abnorml', ['Abnorml', 'AdjLand', 'Alloca', 'Family', 'Normal', 'Partial']], 'SaleCondition_AdjLand': ['SaleCondition', 'AdjLand', ['Abnorml', 'AdjLand', 'Alloca', 'Family', 'Normal', 'Partial']], 'SaleCondition_Alloca': ['SaleCondition', 'Alloca', ['Abnorml', 'AdjLand', 'Alloca', 'Family', 'Normal', 'Partial']], 'SaleCondition_Family': ['SaleCondition', 'Family', ['Abnorml', 'AdjLand', 'Alloca', 'Family', 'Normal', 'Partial']], 'SaleCondition_Normal': ['SaleCondition', 'Normal', ['Abnorml', 'AdjLand', 'Alloca', 'Family', 'Normal', 'Partial']], 'SaleCondition_Partial': ['SaleCondition', 'Partial', ['Abnorml', 'AdjLand', 'Alloca', 'Family', 'Normal', 'Partial']]}
Number of used features in the model (before the encoding of categorical features): 45
Number of used features in the model (after the encoding of categorical features): 151
----------------------------------------------
instance: MSSubClass_20 0
MSSubClass_30 0
MSSubClass_40 0
MSSubClass_45 0
MSSubClass_50 0
..
SaleCondition_AdjLand 0
SaleCondition_Alloca 0
SaleCondition_Family 0
SaleCondition_Normal 1
SaleCondition_Partial 0
Name: 0, Length: 179, dtype: int64
prediction: 195191.86
delta1: 43351.5540875
delta2: 86703.108175
delta3: 173406.21635
delta4: 346812.4327
In order to set correctly the intervals, we use the compute_delta function in order to compute the delta values. A delta value is the quantity to be removed or added to calculate the interval $[a,b]$ as a percentage of the model extreme regression values (minimal and maximal values of possible regression values). For example, the prediction for this instance is $199248.22$, delta1 $\approx 46155$ and the interval for the first tree-specific explanation reported above is $[a,b] = [199248.22 - 46155, 199248.22 + 46155]$. This interval corresponds to $2.5\%$ of values in relation to the model extreme regression minimal and maximal values.
The results are presented in the PyXAI’s GUI thanks to the last lines of explainer.visualisation.gui()

We can observe that the larger the interval I (the percentage and the delta value), the smaller the reason, both in terms of the number of binary variables and the number of features:
- For $2.5\%$, the tree specific explanation has $45$ binary variables and $34$ features
- For $5\%$, the tree specific explanation has $44$ binary variables and $32$ features
- For $10\%$, the tree specific explanation has $35$ binary variables and $27$ features
- For $20\%$, the tree specific explanation has $20$ binary variables and $15$ features
This observation applies to all datasets. The larger the interval, the smaller the explanation. We therefore recommend testing several possible intervals, depending on the problem and possible regression values.