Table 1 Algorithm characteristics and mean ranking scores of Task 1 submissions

From: Towards fair decentralized benchmarking of healthcare AI algorithms with the Federated Tumor Segmentation (FeTS) challenge

Team

Aggregation method

lr schedule

Client selection

Score

 

DS

PD

LO

LI

Combination

   

FLSTAR

 

 

Constant

6 largest

2.75

Sanctuary

 

Polynomial

Alternating: all; drop slow clients

3.05

RoFL

  

+ server optimizer

Step

All

3.35

gauravsingh

  

Constant

6 random

3.67

rigg

 

(weighted)

Constant

Randomly drop large clients

4.65

HT-TUAS

  

Constant

4 random

4.69

Flair

   

Multiple gradient descent with contraint

Constant

All

5.85

  1. Algorithm characteristics include the aggregation method, learning rate (lr) schedule, and client selection. Algorithms are listed in the order of ranking score contained in the Score column, with the best on top. See the methods section for how the ranking score is calculated. A common pattern for aggregation methods is to compute multiple normalized weight terms (DS Dataset size, PD (inverse) Parameter distance, LO Potential for local optimization, LI Local improvement) and combine them either through arithmetic mean () or multiplicative averaging (). The weight term abbreviations were introduced here as categories summarizing the main idea behind the weight terms, but the implementation details in the teams’ algorithms differed slightly, as described in the methods section. Only one team chose a completely different aggregation approach (Flair). Selectively sampling clients was used by five teams to improve the convergence speed.