How to use AI to rank lots by expected bids

Nov 18, 2023

Unlocking Higher Returns: Using AI to Predict and Rank Auction Lots by Expected Bids

Effective lot ranking can be a game-changer for auctioneers and resellers. Knowing which items are likely to attract the most bids helps with everything from catalog layout to marketing prioritization and reserve price setting. With the ever-increasing volume of auction data, artificial intelligence (AI) offers a powerful way to accurately forecast which lots will perform best. Here’s how you can leverage AI to review historical performance and rank lots by expected bids, storing those insights in your backend to fuel smarter sales strategies.

Why Rank Lots by Expected Bids?

  • Strategic Catalog Placement: Positioning high-traffic lots at key points can boost bidder engagement throughout your sale.

  • Marketing Focus: Prioritize promotion for lots with the highest potential, maximizing your advertising ROI.

  • Reserve and Starting Bids: Data-backed rankings give you confidence to set optimal reserves and opening prices.

  • Efficient Operations: Streamline your planning and resource allocation by knowing which lots deserve extra attention.

Step 1: Collect and Prepare Your Historical Data

AI models rely on robust, well-organized data. Start by gathering auction results, including:

  • Lot titles and descriptions

  • Categories and item types

  • Final hammer prices

  • Number of bids and unique bidders per lot

  • Sale dates, reserve prices, and other metadata

Clean your data to remove duplicates and correct inconsistencies. The more granular and accurate your data, the better your AI will perform.

Step 2: Feature Engineering—What Makes a Lot Perform?

AI thrives when you feed it meaningful features. Consider variables beyond just past bid counts:

  • Lot specifics: Brand, condition, rarity, provenance

  • Presentation: Quality of photos, video, and listing copy

  • Seasonality: Are certain items hotter at specific times of year?

  • Market trends: Use external data (e.g., commodity prices or trending collectibles) for context

Tools like Gavelbase help centralize and normalize this information, making it easier to feed into AI models.

Step 3: Choose an AI Approach

For ranking lots by expected bids, most resellers will benefit from supervised machine learning models. These can include:

  • Regression: Predict the number of bids as a continuous variable

  • Classification: Categorize lots into performance tiers (e.g., high, medium, low expected bids)

  • Ranking algorithms: Directly optimize the order in which lots are likely to perform

Python libraries such as scikit-learn, XGBoost, and LightGBM are excellent for building these models. For those less technically inclined, services like Google AutoML and Microsoft Azure ML offer no-code interfaces that can ingest CSVs and quickly generate predictions.

Step 4: Train and Test Your Model

  1. Split your data: Use 70-80% for training, the rest for validation/testing.

  2. Train: Fit your chosen model using historical features and the number of bids as your target variable.

  3. Validate: Test on your holdout set. Use metrics like mean absolute error or ROC-AUC (for classification) to gauge accuracy.

Iterate by adding or refining features, adjusting parameters, or trying different modeling techniques until you achieve reliable predictions.

Step 5: Predict and Rank Future Lots

Once you’re confident in your model, apply it to your upcoming catalog. For each future lot, the AI will output an expected number of bids (or a probability score for bid tiers). Sort your lots accordingly to generate your ranked list.

Step 6: Store Rankings in Your Backend

It’s critical that your rankings aren’t just used in the moment—they should be stored and accessible for ongoing planning. Here’s how:

  • Database Integration: Store predicted bid counts and ranking scores as new fields in your lot records.

  • APIs: If your auction software supports custom APIs, push ranking data automatically after each prediction run.

  • Data Warehouse: For larger operations, use a cloud data warehouse (e.g., BigQuery, Snowflake) to archive predictions for longitudinal analysis.

Storing this data means you can track model accuracy over time, refine strategies, and even automate aspects of catalog planning.

Step 7: Use Insights to Drive Sales Success

With lots ranked by expected bids, apply your insights to:

  • Catalog sequencing—Open with a high-interest lot to build momentum

  • Targeted marketing—Allocate more ad spend to the most promising lots

  • Seller consultations—Advise consignors on expected performance with confidence

  • Reserve price setting—Avoid under- or over-pricing based on objective forecasts

Practical Tips and Best Practices

  • Update your model regularly: Market dynamics change. Retrain your AI on recent sales for ongoing accuracy.

  • Combine AI with expert judgement: Use predictions as a guide, but let experienced staff review and adjust as needed.

  • Visualize results: Dashboards or ranking tables make it easy to interpret and share insights with your team.

  • Start simple: Even basic models can reveal powerful patterns. Don’t let perfectionism delay adoption.

Recommended Tools and Resources

  • Gavelbase – Centralizes auction data and supports AI-driven analysis for lot ranking

  • Scikit-learn – Popular open-source machine learning library

  • Google AutoML – No-code ML model creation

  • Azure ML – Cloud-based ML platform

  • Kaggle – Datasets and tutorials for hands-on machine learning practice

Conclusion

Incorporating AI into your auction or resale business provides a clear edge in ranking lots by expected bids. With the right historical data, a thoughtfully engineered model, and robust backend integration, you’ll be equipped to plan more profitable sales and deliver better results for clients and consignors. As the industry evolves, those who embrace data-driven forecasting and ranking will be best positioned to outperform the competition.