EIP-1: Reputation Score Algorithm Update v1.0.8

Summary

At the highest level, this rebalances scores towards Reviews and away from Mutual vouches. Specifically reviews from highly credible people will be weighted higher.

This update involves two primary modifications:

1. An increase in the maximum positive score impact obtainable from the Review Impact factor.
2. A decrease in the multiplier applied for the Mutual Vouch Bonus.

These changes aim to rebalance scoring factors based on observed data and platform evolution.

Motivation

Analysis of score distributions and factor contributions under the previous algorithm version (v1.0.7) indicated areas for refinement:

1. Review Impact Saturation: Highly reputable users receiving numerous positive reviews often approached the maximum positive score contribution from this factor (+270). This limited the ability of the score to differentiate further based on continued positive feedback and potentially undervalued sustained positive engagement measured through reviews.
2. Mutual Vouch Weighting: The existing Mutual Vouch Bonus multiplier (0.5) significantly amplified the score impact of reciprocal vouches. While mutual trust is valuable, this weighting might have disproportionately inflated scores for tightly-knit pairs compared to broader reputation signals, potentially overshadowing the impact of reviews or other vouching patterns.

This update seeks to address these points by allowing for greater positive influence from reviews while reducing the specific bonus for mutual vouches, aiming for a more balanced reflection of overall reputation.

Specification

The following scoring parameters have been modified effective v1.0.8:

1. REVIEW_IMPACT Range:

   • Previous Maximum: 270
   • New Maximum: 540
   • Minimum Value: Unchanged (-800)

2. REVIEW_IMPACT_ELO_SCALE

   • ELO Model: Adopting an ELO-like formula provides a standard mechanism for comparing ratings where the difference is key. Higher differences lead to exponentially higher (or lower) weights.
   • ELO_SCALE = 1600: A standard chess ELO scale often uses a denominator around 400, meaning a 400-point difference corresponds to a 10x change in expected outcome/weight. Choosing 1600 significantly dampens this effect for the Ethos context. A 1600-point score difference is required for a 10x weight multiplier, making the system less sensitive to smaller score variations compared to traditional ELO but still emphasizing reviews from users with vastly different reputation levels.

The previous ratio-based weighting system (coefficient = (authorScore / subjectScore)^2) had certain characteristics: * It treated relative score differences proportionally regardless of absolute score level (e.g., a review from a score 1600 user on an 800 user had the same initial ratio as a 2000 user on a 1000 user).

3. mutualVouchMultiplier:
   • Previous Value: 0.5 (representing a 50% bonus on the base vouch impact for mutual vouches)
   • New Value: 0.2 (representing a 20% bonus on the base vouch impact for mutual vouches)

Impact

*   **General Score Increase:** Most users experienced an increase in their overall score. This is primarily driven by the increased potential impact from positive reviews outweighing the reduction in the mutual vouch bonus for many users.
*   **Top Performers Boosted:** Users with significant positive review histories (e.g., ZachXBT, Ethos, DeeZe, IcoBeast) saw substantial score gains, reflecting the increased cap on `Review Impact`.
*   **Mutual Vouch Impact Reduced:** The `Mutual Vouch Bonus` component of scores decreased across the board, aligning with the reduced multiplier.
*   **Level Shifts:** Some users transitioned to higher reputation levels (e.g., from Reputable to Exemplary) due to the net positive score change.
*   **Minimal Negative Impact:** The largest score decreases observed were minimal, suggesting the reduction in the mutual vouch bonus did not drastically penalize users compared to the gains from the review impact changes.