← The evidence ledger
Evidence row 2201658
Observed , by sync.x402_bazaar/1.
- Kind
- listing
- About
- source_record x402_bazaar:https://linear-algebra.x402tookit.com/least-squares
- Recorded
- Previous row
- None: the first of its kind about this subject
- Body SHA-256
- f5511991d7932eab31175956ef3254d32a4531765e8f1d6243bf067f803e7254
- Leaf
- 0xc1b8c19ad1fb1b69580dcd4854b6632b71c9149be019eb97625ae46409dea6c2
What was observed
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"name": "Linear Algebra",
"owner_address": "0xb531320805c5bed1d46aeadcf4f008fdf172dbda",
"raw": {
"accepts": [
{
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"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
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{
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{
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"network": "eip155:42161",
"payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
"scheme": "exact"
}
],
"description": "Least-squares line or polynomial fit (degree 1 to 6, up to 100 points) with coefficients, R-squared and residuals.",
"extensions": {
"bazaar": {
"info": {
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"queryParams": {
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"x": "[1,2,3,4]",
"y": "[6,5,7,10]"
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"asOf": "2026-10-12T00:51:55.720Z",
"coefficientOrder": "ascending powers: c0 + c1*x + c2*x^2 + ...",
"coefficients": [
3.5,
1.4
],
"conditioning": {
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"halfRange": 1.5,
"note": "the fit is solved in t = (x - centre)/halfRange for accuracy and converted back"
},
"degraded": false,
"degree": 1,
"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
"fitted": [
4.9,
6.3
],
"intercept": 3.5,
"notChecked": [
"whether a polynomial is the right model (high degree on few points overfits)",
"outliers, heteroscedasticity and the statistical significance of the coefficients",
"…1 more"
],
"points": 4,
"rSquared": 0.7,
"reasons": [
"Householder QR on the (centred and scaled) Vandermonde matrix: minimises the sum of squared vertical residuals.",
"R-squared is 1 minus residual sum of squares over total sum of squares; it is null when all y are equal.",
"…1 more"
],
"residualStandardError": 1.44913767462,
"residuals": [
1.1,
-1.3
],
"rmse": 1.0246950766,
"slope": 1.4,
"source": "computed locally",
"sumSquaredResiduals": 4.2,
"summary": "Degree 1 least-squares fit of 4 points, R-squared 0.7.",
"verdict": "FIT_COMPUTED"
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"rSquared": {
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},
"lastUpdated": "2026-11-01T23:34:04.516Z",
"quality": {
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"l30DaysUniquePayers": 2,
"lastCalledAt": "2026-11-01T23:34:04.356Z"
},
"resource": "https://linear-algebra.x402tookit.com/least-squares",
"serviceName": "Linear Algebra",
"tags": [
"least-squares",
"regression",
"polynomial-fit",
"curve-fit"
],
"type": "http",
"x402Version": 2
},
"source": "x402_bazaar",
"summary": "Least-squares line or polynomial fit (degree 1 to 6, up to 100 points) with coefficients, R-squared and residuals."
}What the leaf hashes
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- Day root
- 0x78fecaabbe319e56f5c4b80fc02e2052e198ad24781da8832a475ff65f2002d1
- Chained
- 0xdc35957db5d1371ca382b9152878ffece28ec7c5cb4f98fd71ddb367f8b999b2
- Published
- On Arc Testnet, block 70432815: 0x56b814612eb2e3e544153df3e91e1f7199106d1e430c7d8c6b653feeb9ebe9af