---
title: Reference models
description: Standard recommender models available in Luigi's Box, from similar products to trending items.
slug: recommendations/models
docKind: concept
hub: recommendations
---

Luigi's Box offers a wide scale of standard recommender models. Each model needs to be trained first. Once set up, you will be given the `recommender_type` to use in recommendation requests described in the [API section](/recommendations/api/v1/recommender/). Contact [support](mailto:support@luigisbox.com) to discuss the options in detail.

Each recommender is personalized for users who granted cookie consent. The models consider user preferences based on the sent user identifier (`user_id`) and boost products with characteristics similar to the user's past interactions.

## Standard models

| Model title | `recommender_type` | Description | Location | Input |
| :--- | :--- | :--- | :--- | :--- |
| Test | `test_reco` | Simple, most popular recommender to test client requests. | Arbitrary | None |
| Similar products | `item_detail_alternatives` | Similar/alternative products, preferring slightly more expensive ones (upsell). | PDP | product id, user id (optional) |
| Visually similar products | `item_detail_visual_alternatives` | Visually similar products based on product images. | PDP | product id, user id (optional) |
| Related complementary products | `item_detail_complements` | Products usually bought together (cross-sell), preferring cheaper products. | PDP | product id, user id (optional) |
| Basket popup complements | `basket_popup` | Cross-sell for the most recently added basket item. | Basket popup | product id, user id (optional) |
| Basket complements | `basket` | Cross-sell for all products in the basket. | Basket detail | product ids, user id (optional) |
| Favorites | `favorites` | Products most likely to be repeatedly bought. Suitable for consumable products. | Homepage, basket | user id |
| Conversion-based | `user_conversion_based` | Products related to past purchases, or trends for new users. | Homepage, 404 | user id |
| Click-based | `user_click_based` | Products similar to recently clicked but not bought items. | Homepage, 404 | user id |
| Top category products | `category` | Trending products from a specific category, diversified by subcategories. | PLP | category id, user id (optional) |
| Top brand products | `brand` | Trending products from a specific brand, diversified by categories. | PLP | brand id, user id (optional) |
| Top user categories | `top_categories` | Most relevant categories for the user. | Homepage, 404 | user id |
| Trends | `trends` | Most popular products overall. | Homepage, 404 | user id (optional) |
| Novel products | `news` | Novel products based on `_introduced_at` date. | Homepage, PLP | user id (optional) |
| Novel products by label | `news_by_label` | Popular products with `"label": "is_new"`. | Homepage, PLP | user id (optional) |
| Discounted products | `discount` | Discounted products based on `price_amount` and `price_old_amount`. | Homepage, PLP | user id (optional) |
| Discounted by label | `discount_by_label` | Popular products with `"label": "is_sale"`. | Homepage, PLP | user id (optional) |
| Recently visited | `last_seen` | Products most recently visited, excluding already bought ones. | Arbitrary | user id |
| Recently visited (same category) | `item_detail_last_seen` | Recently visited products from the same category as the input product. | Arbitrary | user id |
| Recently ordered | `recently_ordered` | Products most recently ordered by a user. | Arbitrary | user id |
| Article related products | `article_items` | Most relevant products based on an article/blog post. | Article detail | article id, user id (optional) |
| Article related articles | `article_articles` | Most relevant articles based on an article/blog post. | Article detail | article id, user id (optional) |
| Random products | `random` | Random products. More useful when combined with filters. | Arbitrary | user id (optional) |
| Random novel products | `random_news` | Random novel products, primarily up to 30 days old. | Arbitrary | user id (optional) |
| Autocomplete popup | `autocomplete_popup` | Popular products, queries, categories for autocomplete init screen. | Autocomplete | user id (optional) |

## Industry-specific models

Some industry segments have specific model adjustments:

| Segment | Models adjusted | Key difference |
| :--- | :--- | :--- |
| **Books and games** | `item_detail_complements`, `basket`, `basket_popup` | Does not prefer cheaper products; allows same-category recommendations |
| **Food and beverages** | `item_detail_complements`, `basket`, `basket_popup`, `last_seen` | Prefers previously bought products; includes already bought in last_seen |
| **Luxury goods and jewelry** | `item_detail_complements`, `basket`, `basket_popup` | Prefers products of similar price |
| **Pharma, cosmetics, body care** | `item_detail_complements`, `basket`, `basket_popup`, `last_seen` | Prefers products from more different categories; includes already bought in last_seen |