Table 3 Machine learning models and their parameter configurations.

From: An integrated physics-guided machine learning approach for predicting asphalt concrete fracture parameters

Model

Parameter

Value/setting

Description

Data Partitioning

Gradient Boosting

Implementation

scikit-learn

Python library used for model development

10-fold cross-validation (90% train / 10% test per fold)

Number of trees

100

Total estimators in the ensemble

Learning rate

0.1

Step size controlling contribution of each tree

Maximum depth

3

Limits complexity of individual trees

Minimum samples split

2

Minimum number of samples required to split a node

Training fraction

1.0 (full dataset)

Ensures replicable performance

Validation method

k-fold cross-validation

Evaluates model robustness and generalization

AdaBoost

Implementation

scikit-learn

Python library used for model development

10-fold cross-validation (90% train / 10% test per fold)

Base estimator

Decision Tree Regressor

Weak learner for boosting

Number of estimators

50

Total boosting iterations

Learning rate

1

Weight applied to each estimator

Loss function

Linear regression loss

Appropriate for continuous targets

Validation method

k-fold cross-validation

Used for model robustness assessment

Linear Regression

Implementation

scikit-learn

Python library used for model development

10-fold cross-validation (90% train / 10% test per fold)

Regularization

None

Standard linear regression without penalty

Model type

Ordinary Least Squares (OLS)

Direct mapping between inputs and outputs

Validation method

k-fold cross-validation

Consistent with other models for comparison