Case Study

KulinaStock Forecast System

A stock forecasting platform designed to analyze historical inventory usage using forecasting methods such as SES, Holt, and Holt-Winters with accuracy metric evaluation.

Next.js
TypeScript
PostgreSQL
Forecasting
SES
Holt
Holt-Winters
TailwindCSS

System Focus

Forecast Analytics

The platform focuses on forecasting future stock requirements based on historical inventory consumption data.

Forecast Engine

Time Series Models

Multiple forecasting methods are implemented to compare prediction quality and improve decision-making accuracy.

Accuracy Metrics

MAE • MAPE • RMSE

Forecast quality is evaluated using standard statistical error metrics for performance comparison.

Architecture

System Architecture Overview

The system architecture separates frontend dashboard operations, forecasting services, API handling, and persistence layers to improve scalability and maintainability.

Architecture Diagram

Forecast Engine Separation

Forecasting logic is isolated into dedicated processing modules to simplify method comparison and future extensibility.

Modular Backend API

API routes handle forecasting requests, historical data retrieval, and metric calculations independently from the UI layer.

Engineering Decisions

Forecasting Strategy

The forecasting system was designed to support comparative analysis between multiple time-series forecasting algorithms.

Why SES?

Simple Exponential Smoothing is effective for stable datasets without strong trends or seasonal patterns.

Why Holt Method?

Holt forecasting improves prediction quality for datasets containing linear trends over time.

Why Holt-Winters?

Holt-Winters supports trend and seasonality detection for more complex forecasting scenarios.

Why Multiple Metrics?

MAE, MAPE, and RMSE provide different perspectives on forecasting accuracy and prediction error quality.

System Analysis

Use Case Diagram

The use case diagram models interactions between administrators, staff members, and forecasting modules during inventory analysis workflows.

Use Case Diagram

Forecasting Workflow

Users can manage inventory data, input historical stock usage, compare forecasting methods, and evaluate prediction accuracy through centralized dashboard operations.

Database Design

Entity Relationship Diagram

The relational schema is designed to manage inventory items, historical stock usage, user authentication, and forecasting results.

ERD

Database Considerations

  • • Historical stock data is separated into dedicated relational records.
  • • Forecast results are stored independently to support method comparison analysis.
  • • Foreign key constraints maintain relational consistency between items and forecast records.

Forecast Persistence

Forecast outputs and accuracy metrics are persisted for historical evaluation, reporting generation, and future comparison.

Forecast Engine

Prediction Processing

Forecast calculations are executed using multiple time-series methods to evaluate prediction performance and trend behavior.

SES Forecast

Uses weighted averages from previous periods to smooth forecasting fluctuations.

Holt Forecast

Captures linear trend movement to improve medium-term predictions.

Holt-Winters

Supports seasonal forecasting behavior using trend and seasonality components.

Technical Flow

System Workflow Diagrams

The following diagrams illustrate authentication, forecasting execution flow, and inventory prediction processing.

Forecast API Sequence

This sequence diagram demonstrates how forecasting requests are processed through API routes and forecasting engines.

Sequence Diagram

Metrics Evaluation Flow

Forecast outputs are evaluated using MAE, MAPE, and RMSE calculations before results are returned to users.

Forecasting Workflow

This activity diagram illustrates the forecasting process from authentication and data input to prediction generation.

Activity Diagram

Forecast Processing Pipeline

Users authenticate into the dashboard, select forecasting methods, calculate prediction metrics, and store forecast results into the database.

Project Metrics

Technical Overview

3

Forecast Methods

MAE

Error Metric

MAPE

Error Metric

RMSE

Error Metric

Future Improvements

Scalability & Optimization

Advanced Forecast Models

Additional forecasting algorithms such as ARIMA or Prophet can improve prediction flexibility for complex datasets.

Interactive Visualization

Dynamic forecasting charts and real-time analytics dashboards can improve forecasting interpretation.

Automated Parameter Tuning

Forecast accuracy can be improved through automatic alpha, beta, and gamma optimization strategies.

Forecast History Tracking

Historical forecast comparison features can improve analytical validation and reporting workflows.