# Recommendation Systems

> Industrial recommendation systems: recall (DSSM, SASRec, MIND, Swing, ItemCF), pre-ranking (COLD), ranking (DIN, DIEN, BST, DCN V2, DeepFM), re-ranking (PLE, MMOE, DPP), multi-task learning, feature engineering for CTR, and real-time serving architecture. Covers the full recall→pre-rank→rank→re-rank pipeline used at top tech companies. Use when building recommendation, search ranking, or ad syste…

- **Type:** Skill
- **Install:** `agentstack add skill-ericwang915-data-scientist-skills-recommendation-systems`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [ericwang915](https://agentstack.voostack.com/s/ericwang915)
- **Installs:** 0
- **Category:** [Search](https://agentstack.voostack.com/c/search)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [ericwang915](https://github.com/ericwang915)
- **Source:** https://github.com/ericwang915/data-scientist-skills/tree/main/ds-machine-learning/skills/recommendation-systems

## Install

```sh
agentstack add skill-ericwang915-data-scientist-skills-recommendation-systems
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Recommendation Systems

## Purpose
Design and build industrial-grade recommendation systems using the multi-stage architecture adopted by Alibaba, ByteDance, Google, Meta, and other top tech companies.

## How It Works

### System Architecture (Industrial Standard)

```
┌──────────────────────────────────────────────────────┐
│                    User Request                       │
├──────────────────────────────────────────────────────┤
│  Stage 1: RECALL (Candidate Generation)               │
│  Input: billions of items → Output: ~1000 candidates  │
│  Models: DSSM, SASRec, MIND, Swing, ItemCF, ANN      │
│  Latency budget:  50. Use MMOE for CTR + CVR multi-task.
```

```
"Our recommendation system has a 'filter bubble' problem —
users keep seeing the same categories"
→ Add DPP diversity re-ranking, exploration channels in recall,
  category-aware negative sampling, position-debiased training
```

## Output Format

- **System Architecture**: Multi-stage pipeline with model choices per stage
- **Model Code**: PyTorch implementation with training loop
- **Feature Schema**: Feature list with types and encoding strategy
- **Offline Evaluation**: AUC, GAUC, NDCG, HitRate@K metrics
- **Online Metrics**: CTR, CVR, GMV, diversity, coverage, novelty
- **Serving Design**: Latency budget, ANN index, feature store

---

### Key References
- Zhou et al. (2018) — *DIN: Deep Interest Network for Click-Through Rate Prediction* (Alibaba)
- Zhou et al. (2019) — *DIEN: Deep Interest Evolution Network* (Alibaba)
- Chen et al. (2019) — *BST: Behavior Sequence Transformer for E-commerce Recommendation* (Alibaba)
- Wang et al. (2021) — *DCN V2: Improved Deep & Cross Network* (Google)
- Ma et al. (2018) — *MMOE: Modeling Task Relationships in Multi-Task Learning* (Google)
- Tang et al. (2020) — *PLE: Progressive Layered Extraction for Multi-Task Learning* (Tencent)
- Huang et al. (2013) — *DSSM: Learning Deep Structured Semantic Models* (Microsoft)
- Kang & McAuley (2018) — *SASRec: Self-Attentive Sequential Recommendation* (UCSD)
- Pi et al. (2020) — *SIM: Search-based Interest Model* (Alibaba)
- Guo et al. (2017) — *DeepFM: A Factorization-Machine based Neural Network* (Huawei)

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [ericwang915](https://github.com/ericwang915)
- **Source:** [ericwang915/data-scientist-skills](https://github.com/ericwang915/data-scientist-skills)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-ericwang915-data-scientist-skills-recommendation-systems
- Seller: https://agentstack.voostack.com/s/ericwang915
- Browse the marketplace: https://agentstack.voostack.com/browse

---
Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.