Mpesa mobile application built using MIT App Inventor
# Mpesa Fraud Detection System
## ๐ Overview
This project is a mobile-based fraud detection system built using **MIT App Inventor**. It simulates fraud detection in mobile money transactions using a **hybrid approach combining rule-based detection and a Naive Bayes probabilistic model (conceptual/extended).**
The system also uses **TinyDB for local data storage** to record and analyze transaction history.
---
## ๐จ Problem Statement
Mobile money platforms are vulnerable to fraudulent activity such as:
- Suspicious transaction behavior
- Repeated unauthorized transfers
- Social engineering-based fraud patterns
This system demonstrates how fraud can be detected using a combination of **keyword-based rules and probability-based classification concepts**.
---
## โ๏ธ Features
### ๐น Rule-Based Detection (Keyword Pattern Matching)
The system uses predefined **fraud-related and genuine keywords** to evaluate transactions.
- Fraud indicators include suspicious or high-risk keywords
- Genuine keywords indicate normal or trusted behavior
- Transactions are analyzed based on the presence of these words
If fraud-related keywords are detected, the system flags the transaction as **potentially suspicious**.
---
### ๐น Naive Bayes Probabilistic Model (Conceptual Layer)
The system is extended with a **Naive Bayes machine learning concept** to estimate fraud probability based on transaction patterns.
This model evaluates the likelihood of fraud using:
- Transaction behavior patterns
- Frequency of activity
- Keyword occurrence probability
- Historical classification trends
:contentReference[oaicite:0]{index=0}
### Purpose:
- Assign probability scores to transactions
- Improve decision-making beyond simple keyword rules
- Demonstrate machine learning enhancement potential
---
### ๐น Data Storage (TinyDB)
- Stores transaction records locally on the device
- Maintains history for comparison and analysis
- Supports rule-based and conceptual ML evaluation
---
## ๐ ๏ธ Tools Us โฆ