In the fast-advancing domains of artificial intelligence and machine learning,the need for models capable of efficiently handling large, complex datasets is inevitable.
Traditional methods such as decision trees and nearest-neighbor algorithms
often struggle with computational complexity and scalability when applied to highdimensional
data, especially in domains like agriculture, where large amounts of realtime
data are generated from sensor networks. These challenges require the development
of more efficient learning algorithms that can reduce computational overhead
while maintaining predictive accuracy.
To address these challenges, in this research, we propose a novel Stochastic Decision
Tree (SDT) model that introduces randomness into the tree induction process,
significantly reducing computational complexity while maintaining or improving accuracy.
The proposed method leverages stochasticity to prioritize important features
and efficiently process large datasets. The proposed Neural-SRNN model addresses
class imbalance issues by using a specialized loss function (Focal Loss) to focus on
hard-to-classify instances. We demonstrate the effectiveness of this approach through
empirical evaluations of standard datasets.
In addition, we extend the application of stochastic methods by developing a
Neural-Synthetic Reduced Nearest Neighbor (Neural-SRNN) algorithm, which integrates
neural networks into the SRNN framework to improve performance and interpretability
in high-dimensional classification tasks. This method combines the
flexibility of neural networks with the computational advantages of the SRNN model,
achieving superior performance on image classification benchmarks such as MNIST
and Fashion-MNIST with an expectation-maximization approach.
To preserve the strength of the proposed Neural-SRNN model and improve efficiency and scalability, we proposed a two-layer Neural-SRNN model that builds
on the Synthetic Reduced Nearest-Neighbor (SRNN) architecture. This model uses
a modular approach, employing Mini-Convolutional Neural Networks (Mini-CNNs)
in the first layer to perform class-specific feature extraction, followed by a shallow
neural network for final classification. This two-layer architecture allows for efficient
parallel processing, significantly reducing computational overhead while maintaining
high accuracy. Moreover, it improves generalization and prevents overfitting on complex
datasets such as SignMNIST and FashionMNIST. The two-layer Neural-SRNN
model demonstrates superior accuracy and computational efficiency, demonstrating
its scalability and adaptability to complex, high-dimensional data.
The dissertation further explores the application of the Stochastic Decision tree
technique to real-world agricultural problems, particularly in optimizing water usage
in almond and pistachio orchards. By predicting stem water potential using aerial and
ground sensor data, the SDT model improves irrigation efficiency and contributes to
the development of sustainable agricultural practices. This work advances machine
learning by presenting novel and efficient stochastic algorithms and demonstrating
their practical applicability in critical areas such as agriculture.