Fixes to forum value propagation logic

forum-network/notes/rep.md

@@ -50,9 +50,3 @@ At a minimum this can be a list where each item includes the identifier of the c
 Each validation pool can then keep a record of the reputation staked by each voter, and the identifier of the corresponding post.
 
 ---
-
-So: If some incoming reputation can’t be propagated due to a constraint like this, the question is what should happen with that unspent power. I think right now, I have it so when that limit is reached on leaching from PostA, the extra reputation accrues evenly (because of +0.5 citation) equally to PostX and PostZ.
-
-Intuitively, we might want less value accruing to PostX, as it seems intended as a small utility post to transfer power.
-
-However, we can combine these mechanisms. PostX

forum-network/src/classes/action.js

@@ -5,11 +5,10 @@ export class Action {
   }
 
   async log(src, dest, msg, obj, symbol = '->>') {
-    const logObj = false;
     if (this.scene.sequence) {
       await this.scene.sequence.log(
         `${src.name} ${symbol} ${dest.name} : ${this.name} ${msg ?? ''} ${
-          logObj && obj ? JSON.stringify(obj) : ''
+          JSON.stringify(obj) ?? ''
         }`,
       );
     }

forum-network/src/classes/forum.js

@@ -4,7 +4,7 @@ import { Action } from './action.js';
 import { CryptoUtil } from './crypto.js';
 import params from '../params.js';
 import { ReputationHolder } from './reputation-holder.js';
-import { displayNumber } from '../util.js';
+import { displayNumber, EPSILON } from '../util.js';
 
 const CITATION = 'citation';
 const BALANCE = 'balance';
@@ -20,10 +20,19 @@ class Post extends Actor {
     this.initialValue = 0;
     this.citations = postContent.citations;
     this.title = postContent.title;
-    const revaluationTotal = this.citations.reduce((total, { weight }) => total += Math.abs(weight), 0);
-    if (revaluationTotal > params.revaluationLimit) {
-      throw new Error('Post revaluation total exceeds revaluation limit '
-      + `(${revaluationTotal} > ${params.revaluationLimit})`);
+    const leachingTotal = this.citations
+      .filter(({ weight }) => weight < 0)
+      .reduce((total, { weight }) => total += -weight, 0);
+    const donationTotal = this.citations
+      .filter(({ weight }) => weight > 0)
+      .reduce((total, { weight }) => total += weight, 0);
+    if (leachingTotal > params.revaluationLimit) {
+      throw new Error('Post leaching total exceeds revaluation limit '
+      + `(${leachingTotal} > ${params.revaluationLimit})`);
+    }
+    if (donationTotal > params.revaluationLimit) {
+      throw new Error('Post donation total exceeds revaluation limit '
+      + `(${donationTotal} > ${params.revaluationLimit})`);
     }
     if (this.citations.some(({ weight }) => Math.abs(weight) > 1)) {
       throw new Error('Each citation weight must be in the range [-1, 1]');
@@ -130,11 +139,24 @@ export class Forum extends ReputationHolder {
    * @param {Edge} edge
    * @param {Object} opaqueData
    */
-  async propagateValue(edge, { rewardsAccumulator, increment, depth = 0 }) {
+  async propagateValue(edge, {
+    rewardsAccumulator, increment, depth = 0, initialNegative = false,
+  }) {
     const postVertex = edge.to;
     const post = postVertex?.data;
+    const balanceFromInbound = this.posts.getEdgeWeight(BALANCE, edge.from, edge.to) ?? 0;
+    this.actions.propagateValue.log(edge.from.data, post, `(${increment}) balance (${balanceFromInbound})`);
 
-    this.actions.propagateValue.log(edge.from.data, post, `(${increment})`);
+    if (!!params.referenceChainLimit && depth > params.referenceChainLimit) {
+      this.actions.propagateValue.log(
+        edge.from.data,
+        post,
+        `referenceChainLimit (${params.referenceChainLimit}) reached`,
+        null,
+        '-x',
+      );
+      return increment;
+    }
 
     console.log('propagateValue start', {
       from: edge.from.id,
@@ -142,58 +164,37 @@ export class Forum extends ReputationHolder {
       depth,
       value: post.value,
       increment,
+      balanceFromInbound,
+      initialNegative,
     });
 
-    if (params.referenceChainLimit === null || depth <= params.referenceChainLimit) {
-      let totalOutboundAmount = 0;
-      let totalRefundFromOutbound = 0;
-      for (const citationEdge of postVertex.getEdges(CITATION, true)) {
-        const { to: citedPostVertex, weight } = citationEdge;
-        let outboundAmount = weight * increment;
-        const balanceEdge = this.posts.getEdge(BALANCE, postVertex, citedPostVertex);
-        const balance = balanceEdge?.weight ?? 0;
-        // We need to ensure that we propagate no more reputation than we leached
-        if (depth > 0 && weight < 0) {
-          outboundAmount = outboundAmount < 0
-            ? Math.max(outboundAmount, -balance)
-            : Math.min(outboundAmount, -balance);
-        }
+    let totalOutboundAmount = 0;
+
+    for (const citationEdge of postVertex.getEdges(CITATION, true)) {
+      const { weight } = citationEdge;
+      let outboundAmount = weight * increment;
+      const balanceToOutbound = this.posts.getEdgeWeight(BALANCE, citationEdge.from, citationEdge.to) ?? 0;
+      // We need to ensure that we propagate no more reputation than we leached
+      if (initialNegative) {
+        outboundAmount = outboundAmount < 0
+          ? Math.max(outboundAmount, -balanceToOutbound)
+          : Math.min(outboundAmount, -balanceToOutbound);
+      }
+      if (Math.abs(outboundAmount) > EPSILON) {
         const refundFromOutbound = await this.propagateValue(citationEdge, {
           rewardsAccumulator,
           increment: outboundAmount,
           depth: depth + 1,
+          initialNegative: initialNegative || (depth === 0 && outboundAmount < 0),
         });
-        totalRefundFromOutbound += Math.abs(refundFromOutbound);
         outboundAmount -= refundFromOutbound;
-        this.posts.setEdgeWeight(BALANCE, postVertex, citedPostVertex, balance + outboundAmount);
-
+        this.posts.setEdgeWeight(BALANCE, citationEdge.from, citationEdge.to, balanceToOutbound + outboundAmount);
         totalOutboundAmount += outboundAmount;
       }
-
-      // Now that we know what value could not be propagated as negative citations,
-      // Let's see what happens if we redistribute it among the positive citations :)
-
-      const positiveCitations = postVertex.getEdges(CITATION, true).filter(({ weight }) => weight > 0);
-      const totalPositiveCitationWeight = positiveCitations.reduce((total, { weight }) => total += weight, 0);
-
-      for (const citationEdge of positiveCitations) {
-        const { to: citedPostVertex, weight } = citationEdge;
-        const outboundAmount = totalRefundFromOutbound * (weight / totalPositiveCitationWeight);
-        const balance = this.posts.getEdgeWeight(BALANCE, postVertex, citedPostVertex) ?? 0;
-        await this.propagateValue(citationEdge, {
-          rewardsAccumulator,
-          increment: outboundAmount,
-          depth: depth + 1,
-        });
-        this.posts.setEdgeWeight(BALANCE, postVertex, citedPostVertex, balance + outboundAmount);
-        totalOutboundAmount += outboundAmount;
-      }
-
-      // And what if they don't have any positive citations? The value should just accrue to this post.
-
-      increment -= totalOutboundAmount * params.leachingValue;
     }
 
+    increment -= totalOutboundAmount * params.leachingValue;
+
     const rawNewValue = post.value + increment;
     const newValue = Math.max(0, rawNewValue);
     const appliedIncrement = newValue - post.value;

forum-network/src/classes/reputation-token.js

@@ -1,7 +1,7 @@
 import { ERC721 } from './erc721.js';
 import { CryptoUtil } from './crypto.js';
 
-const EPSILON = 2.23e-16;
+import { EPSILON } from '../util.js';
 
 class Lock {
   constructor(tokenId, amount, duration) {

forum-network/src/classes/scene.js

@@ -135,7 +135,6 @@ export class Scene {
     const logBox = this.box.addBox('Flowchart text').addClass('dim');
     this.flowchart = new MermaidDiagram(box, logBox);
     this.flowchart.log(`graph ${direction}`, false);
-    this.flowchart.log(`classDef edge fill:${this.options.edgeNodeColor}`, false);
     return this;
   }
 
@@ -148,7 +147,6 @@ export class Scene {
     const logBox = container.addBox('Flowchart text').addClass('dim');
     const flowchart = new MermaidDiagram(box, logBox);
     flowchart.log(`graph ${direction}`, false);
-    this.flowchart.log(`classDef edge fill:${this.options.edgeNodeColor}`, false);
     this.flowcharts.set(id, flowchart);
     return this;
   }

forum-network/src/classes/wdag.js

@@ -70,34 +70,25 @@ export class WDAG {
     return Array.from(this.vertices.values()).map(({ data }) => data);
   }
 
-  getEdgeLabel(label) {
-    return this.edgeLabels.get(label);
-  }
-
-  getOrCreateEdgeLabel(label) {
-    let edges = this.getEdgeLabel(label);
-    if (!edges) {
-      edges = new Map();
-      this.edgeLabels.set(label, edges);
-    }
-    return edges;
+  static getEdgeKey({ from, to }) {
+    return btoa([from.id, to.id]).replaceAll(/[^A-Z]+/g, '');
   }
 
   getEdge(label, from, to) {
     from = from instanceof Vertex ? from : this.getVertex(from);
     to = to instanceof Vertex ? to : this.getVertex(to);
+    if (!from || !to) {
+      return undefined;
+    }
     const edges = this.edgeLabels.get(label);
-    return edges?.get(JSON.stringify([from.id, to.id]));
+    const edgeKey = WDAG.getEdgeKey({ from, to });
+    return edges?.get(edgeKey);
   }
 
   getEdgeWeight(label, from, to) {
     return this.getEdge(label, from, to)?.weight;
   }
 
-  static getEdgeKey({ from, to }) {
-    return btoa([from.id, to.id]).replaceAll(/[^A-Z]+/g, '');
-  }
-
   getEdgeHtml({ from, to }) {
     let html = '<table>';
     for (const { label, weight } of this.getEdges(null, from, to)) {
@@ -109,7 +100,7 @@ export class WDAG {
 
   getEdgeFlowchartNode(edge) {
     const edgeKey = WDAG.getEdgeKey(edge);
-    return `${edgeKey}(${this.getEdgeHtml(edge)}):::edge`;
+    return `${edgeKey}(${this.getEdgeHtml(edge)})`;
   }
 
   setEdgeWeight(label, from, to, weight) {
@@ -137,6 +128,7 @@ export class WDAG {
     from.edges.from.push(edge);
     to.edges.to.push(edge);
     this.flowchart?.log(`${from.id} --- ${this.getEdgeFlowchartNode(edge)} --> ${to.id}`);
+    this.flowchart?.log(`class ${WDAG.getEdgeKey(edge)} edge`);
     return this;
   }
 

forum-network/src/index.css

@@ -45,3 +45,6 @@ th {
 td {
   background-color: #0c2025;
 }
+.edge > rect {
+  fill: #216262 !important;
+}

forum-network/src/index.html

@@ -12,7 +12,7 @@
     <li>
       Forum
       <ul>
-        <li><a href="./tests/forum1.test.html">Negative citation of a negative citation with max strength</a></li>
+        <li><a href="./tests/forum1.test.html">Negative citation of a negative citation</a></li>
         <li><a href="./tests/forum2.test.html">Negative citation of a weaker negative citation</a></li>
         <li><a href="./tests/forum3.test.html">Redistribute power</a></li>
         <li><a href="./tests/forum4.test.html">Redistribute power through subsequent support</a></li>

forum-network/src/tests/scripts/forum.test-util.js

@@ -7,16 +7,18 @@ import { Forum } from '../../classes/forum.js';
 import { PostContent } from '../../classes/post-content.js';
 import params from '../../params.js';
 
-const DEFAULT_DELAY_MS = 1;
-const POOL_DURATION_MS = 50;
-
 export class ForumTest {
-  constructor() {
+  constructor(options) {
     this.scene = null;
     this.forum = null;
     this.bench = null;
     this.experts = null;
     this.posts = null;
+    this.options = {
+      defaultDelayMs: 1,
+      poolDurationMs: 50,
+      ...options,
+    };
   }
 
   async newExpert() {
@@ -44,15 +46,15 @@ export class ForumTest {
       postContent,
       {
         fee,
-        duration: POOL_DURATION_MS,
+        duration: this.options.poolDurationMs,
         tokenLossRatio: 1,
       },
     );
     this.posts.push(postId);
-    await delay(POOL_DURATION_MS);
+    await delay(this.options.poolDurationMs);
     await pool.evaluateWinningConditions();
     await this.scene.endSection();
-    await delay(DEFAULT_DELAY_MS);
+    await delay(this.options.defaultDelayMs);
     return postId;
   }
 

forum-network/src/tests/scripts/forum1.test.js

@@ -7,7 +7,7 @@ describe('Forum', () => {
     await forumTest.setup();
   });
 
-  context('Negative citation of a negative citation with max strength', async () => {
+  context('Negative citation of a negative citation', async () => {
     it('Post1', async () => {
       const { forum, experts, posts } = forumTest;
       await forumTest.addPost(experts[0], 10);

forum-network/src/tests/scripts/forum3.test.js

@@ -23,13 +23,13 @@ describe('Forum', () => {
 
     it('Post3 cites Post2 and negatively cites Post1', async () => {
       const { forum, experts, posts } = forumTest;
-      await forumTest.addPost(experts[0], 20, [
-        { postId: posts[0], weight: -0.5 },
-        { postId: posts[1], weight: 0.5 },
+      await forumTest.addPost(experts[0], 10, [
+        { postId: posts[0], weight: -1 },
+        { postId: posts[1], weight: 1 },
       ]);
       forum.getPost(posts[0]).value.should.equal(0);
       forum.getPost(posts[1]).value.should.equal(20);
-      forum.getPost(posts[2]).value.should.equal(20);
+      forum.getPost(posts[2]).value.should.equal(10);
     });
   });
 });

forum-network/src/tests/scripts/forum4.test.js

@@ -31,8 +31,8 @@ describe('Forum', () => {
 
     it('Post3 cites Post2 and negatively cites Post1', async () => {
       await forumTest.addPost(experts[0], 0, [
-        { postId: posts[0], weight: -0.5 },
-        { postId: posts[1], weight: 0.5 },
+        { postId: posts[0], weight: -1 },
+        { postId: posts[1], weight: 1 },
       ]);
       forum.getPost(posts[0]).value.should.equal(10);
       forum.getPost(posts[1]).value.should.equal(10);
@@ -40,23 +40,23 @@ describe('Forum', () => {
     });
 
     it('Post4 cites Post3 to strengthen its effect', async () => {
-      await forumTest.addPost(experts[0], 20, [
+      await forumTest.addPost(experts[0], 10, [
         { postId: posts[2], weight: 1 },
       ]);
       forum.getPost(posts[0]).value.should.equal(0);
       forum.getPost(posts[1]).value.should.equal(20);
-      forum.getPost(posts[2]).value.should.equal(20);
+      forum.getPost(posts[2]).value.should.equal(10);
       forum.getPost(posts[3]).value.should.equal(0);
     });
 
     it('Post5 cites Post3 to strengthen its effect', async () => {
-      await forumTest.addPost(experts[0], 20, [
+      await forumTest.addPost(experts[0], 10, [
         { postId: posts[2], weight: 1 },
       ]);
       console.log('test5', { posts });
       forum.getPost(posts[0]).value.should.equal(0);
-      forum.getPost(posts[1]).value.should.equal(20);
-      forum.getPost(posts[2]).value.should.equal(20);
+      forum.getPost(posts[1]).value.should.equal(30);
+      forum.getPost(posts[2]).value.should.equal(10);
       forum.getPost(posts[3]).value.should.equal(0);
       forum.getPost(posts[4]).value.should.equal(0);
     });

forum-network/src/util.js

@@ -1,5 +1,7 @@
 const timers = new Map();
 
+export const EPSILON = 2.23e-16;
+
 export const debounce = async (fn, delayMs) => {
   const timer = timers.get(fn);
   if (timer) {