in a Marketplace [Industrial Applications] Rishabh Mehrotra Ben Carterette Senior Research Scientist, Senior Research Manager, Spotify, London Spotify, New York [email protected][email protected] 23rd August 2020 @erishabh @BenCarterette https://sites.google.com/view/kdd20-marketplace-autorecsys/
Marketplace 3. Methods for Multi-Objective Ranking & Recommendations 4. Leveraging Consumer, Supplier & Content Understanding 5. Industrial Applications a. Recommendation with capacity constraints b. Email volume optimization at LinkedIn c. Click shaping at Yahoo d. Seller side AB testing at Facebook Marketplace e. Feedback shaping to nurture content creation at LinkedIn f. Joint optimization for profit & relevance at Etsy g. Revenue Maximization at AirBnb Search h. Joint Optimization for Music Streaming at Spotify i. Other Applications
capacity constraints 2 key concepts: item capacity & user propensity Weighted objectives: 1. Loss capturing recommendations 2. Capacity loss a. Avg capacity loss: b. 1[.] not suitable for optimization
capacity constraints 2 key concepts: item capacity & user propensity Weighted objectives: 1. Loss capturing recommendations 2. Capacity loss a. Avg capacity loss: b. 1[.] not suitable for optimization c. logistic loss of the difference as the surrogate
drop in engagement More emails → user ignores, drop in brand value Trade-offs: • Minimize # emails sent • Maximize # downstream sessions • Minimize # resulting complaints Gupta, Liang, Tseng, Vijay, Chen and Rosales. Email volume optimization at LinkedIn. KDD 2016
# emails sent • Maximize # downstream sessions • Minimize # resulting complaints MOO formulated as a Constrained linear programming problem (LP) → Gupta, Liang, Tseng, Vijay, Chen and Rosales. Email volume optimization at LinkedIn. KDD 2016 expected number of emails sent for serving plan z
# emails sent • Maximize # downstream sessions • Minimize # resulting complaints MOO formulated as a Constrained linear programming problem (LP) → Gupta, Liang, Tseng, Vijay, Chen and Rosales. Email volume optimization at LinkedIn. KDD 2016 Targets for global & local session counts
# emails sent • Maximize # downstream sessions • Minimize # resulting complaints MOO formulated as a Constrained linear programming problem (LP) → Gupta, Liang, Tseng, Vijay, Chen and Rosales. Email volume optimization at LinkedIn. KDD 2016 Global & local tolerance for complaints
& why are they important? 2. Characterizing Tasks across interfaces: 1. desktop search 2. digital assistants 3. voice-only assistants 3. Understanding User Tasks in Web Search a. Extracting Query Intents b. Queries → Sessions → Tasks c. Search Task Understanding a. Task extraction b. Subtask extraction c. Hierarchies of tasks & subtasks d. Evaluating task extraction algorithms 5. Recommendation Systems a. Case study: Pinterest b. Case study: Spotify Take-home messages: • Traditional RecSys methods are majorly user-centric • Need to explicitly consider other stakeholders • Different types of marketplaces & examples • Components: – Multi-objective methods – User & Content understanding
task & why are they important? 2. Characterizing Tasks across interfaces: 1. desktop search 2. digital assistants 3. voice-only assistants 3. Understanding User Tasks in Web Search a. Extracting Query Intents b. Queries → Sessions → Tasks c. Search Task Understanding a. Task extraction b. Subtask extraction c. Hierarchies of tasks & subtasks d. Evaluating task extraction algorithms 5. Recommendation Systems a. Case study: Pinterest b. Case study: Spotify Take-home messages: • Multiple stakeholders – Multiple objectives per stakeholder • Interplay between objectives: – Neutral / positive / negative • Careful consideration needed to decide which objectives to optimize for
task & why are they important? 2. Characterizing Tasks across interfaces: 1. desktop search 2. digital assistants 3. voice-only assistants 3. Understanding User Tasks in Web Search a. Extracting Query Intents b. Queries → Sessions → Tasks c. Search Task Understanding a. Task extraction b. Subtask extraction c. Hierarchies of tasks & subtasks d. Evaluating task extraction algorithms 5. Recommendation Systems a. Case study: Pinterest b. Case study: Spotify Take-home messages: • Flavors of multi-objective approaches available: – Multi-task learning – Scalarization – MO-Multi task learning – MO-Bandits & MO-RL • Often optimizing for multiple interaction metrics performs better for each metric than directly optimizing that metric • Not necessarily a Zero-Sum Game
is a task & why are they important? 2. Characterizing Tasks across interfaces: 1. desktop search 2. digital assistants 3. voice-only assistants 3. Understanding User Tasks in Web Search a. Extracting Query Intents b. Queries → Sessions → Tasks c. Search Task Understanding a. Task extraction b. Subtask extraction c. Hierarchies of tasks & subtasks d. Evaluating task extraction algorithms 5. Recommendation Systems a. Case study: Pinterest b. Case study: Spotify Take-home messages: • Understanding users helps in pushing other objectives without hurting key user metrics – Consumption diversity – User intents – User receptivity • Understanding suppliers helps develop right approaches to ensure supplier happiness: – Supplier diversity – Spillover effects • Content understanding allows us to know when to focus on what objectives