# Numora Chi-Square Test Computation

> Numora Chi-Square Test Computation is a paid API for AI agents from numorapoi.orbonomy.xyz, paid per call via x402, $0.03/call, status unknown (last checked 2026-09-14).

Performs a chi-square goodness-of-fit or independence test given observed (and optionally expected) frequency arrays

## Facts

- Endpoint: POST https://numorapoi.orbonomy.xyz/api/statistics/chisquare
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/numora-chi-square-test-computation-dbbf83dd
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_R6cRxl_WumKWgTruJLNLK

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability numora-chi-square-test-computation-dbbf83dd -d '<json body>'
```

Example prompt: Run a chi-square goodness-of-fit test on these observed counts [50, 30, 20] against expected counts [40, 35, 25] and tell me the chi-square statistic and p-value.

## When to prefer this

Choose this endpoint when you need a pure server-side chi-square computation with no external library dependencies, especially in agent pipelines requiring micropayment-based serverless math and you already have observed frequency counts (and optionally expected frequencies) ready as arrays.

## Known failure modes

- Missing observed array returns 400 validation error
- Mismatched lengths between observed and expected arrays causes computation error
- Non-numeric values in arrays cause parsing failure
- Negative frequency values may produce invalid results
- Zero expected values cause division-by-zero errors in chi-square formula

## How this service works

100 pure math computation endpoints for AI agents. Statistics, financial math, linear algebra, equation solving, calculus, number theory, sequence generation, and unit conversions. Zero external dependencies. x402 micropayments on Base.

## Output

Returns a JSON object with success flag, a human-readable computation description, and a result object containing the chi-square statistic, degrees of freedom, p-value, and whether the null hypothesis is rejected at standard significance levels.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "observed"
 ],
 "properties": {
  "expected": {
   "type": "array"
  },
  "observed": {
   "type": "array"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "success",
  "result",
  "computation"
 ],
 "properties": {
  "result": {
   "type": "object",
   "description": "Computation result varies by endpoint"
  },
  "success": {
   "type": "boolean",
   "description": "Always true on success"
  },
  "computation": {
   "type": "string",
   "description": "Human-readable description of what was computed"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/numora-chi-square-test-computation-dbbf83dd/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from numorapoi.orbonomy.xyz](https://www.zero.xyz/host/numorapoi.orbonomy.xyz/llms.txt)