# Cohen's d Effect Size Calculator

> Cohen's d Effect Size Calculator is a paid API for AI agents from kihustle.tech, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-14).

Computes Cohen's d effect size statistic between two numeric groups to quantify the magnitude of difference between them

## Facts

- Endpoint: POST https://kihustle.tech/nexus/api/v1/effect-size-cohens-d
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/cohen-s-d-effect-size-calculator-9c3ea74b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kcPU_kOjX4OaVizgY6Dsa

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 cohen-s-d-effect-size-calculator-9c3ea74b -d '<json body>'
```

Example prompt: Calculate Cohen's d effect size between these two groups for me — group A is [2.3, 3.1, 2.8, 3.5, 2.9] and group B is [4.1, 4.8, 3.9, 5.2, 4.5].

## When to prefer this

Choose this endpoint when you need a quick, cheap ($0.002) statistical computation of Cohen's d effect size between two groups without setting up a local statistics library. Ideal for agents automating research reporting, A/B test summarization, or educational assessment pipelines where effect size must be calculated programmatically at scale.

## Known failure modes

- Empty arrays for group_a or group_b may cause computation errors
- Arrays with a single element may produce unreliable standard deviation estimates
- Non-numeric values in arrays will likely cause processing failures
- Extremely large arrays may increase latency
- Missing required fields returns an error status

## How this service works

Kostenlose Guides, Solo-Playbooks und Artikel zu KI, Automation und Side Hustles — für Menschen, die mit echten Systemen online Einkommen aufbauen wollen. Transparent finanziert über faire Affiliate-Links.

## Output

Returns a JSON object with a computed result value (Cohen's d statistic) and a success status indicator. Cohen's d represents the standardized mean difference between the two groups, where 0.2 is considered small, 0.5 medium, and 0.8+ large effect.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "group_a": {
   "type": "array",
   "items": {
    "type": "number"
   }
  },
  "group_b": {
   "type": "array",
   "items": {
    "type": "number"
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": "processed",
  "status": "success"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/cohen-s-d-effect-size-calculator-9c3ea74b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kihustle.tech](https://www.zero.xyz/host/kihustle.tech/llms.txt)