Forge Tools power_calc

power_calc read

scidex.forge.power_calc

Statistical power calculation using scipy.stats (full) or normal-approximation fallback (no scipy needed). Provide ``n`` to compute achieved power. Provide ``power_target`` to compute required sample size.

HTTP: POST /api/scidex/forge/power_calc

Invoke

Calls scidex.tool.invoke on the substrate with this tool name. Edit the JSON below — it must match the input schema. The substrate runs the tool, records the call in substrate_tool_calls, and returns a structured envelope.

Sign in to invoke this tool. Schema and curl snippet are visible to anyone.

Schemas

Input schema 
{
  "description": "Input schema for ``scidex.forge.power_calc``.",
  "properties": {
    "effect_size": {
      "description": "Standardised effect size (Cohen's d for t-tests, Cohen's w for chi2, f for ANOVA). Typical ranges: small=0.2, medium=0.5, large=0.8.",
      "title": "Effect Size",
      "type": "number"
    },
    "n": {
      "anyOf": [
        {
          "minimum": 2,
          "type": "integer"
        },
        {
          "type": "null"
        }
      ],
      "default": null,
      "description": "Sample size per arm (for two_sample/chi2/anova) or total N (for one_sample/paired). Provide either n or target_power, not both.",
      "title": "N"
    },
    "alpha": {
      "default": 0.05,
      "description": "Significance level (type I error rate).",
      "exclusiveMaximum": 1,
      "exclusiveMinimum": 0,
      "title": "Alpha",
      "type": "number"
    },
    "test_type": {
      "default": "two_sample",
      "description": "Type of statistical test.",
      "enum": [
        "two_sample",
        "one_sample",
        "paired",
        "chi2",
        "anova"
      ],
      "title": "Test Type",
      "type": "string"
    },
    "power_target": {
      "anyOf": [
        {
          "exclusiveMaximum": 1,
          "exclusiveMinimum": 0.5,
          "type": "number"
        },
        {
          "type": "null"
        }
      ],
      "default": null,
      "description": "Target power for sample-size computation. Use instead of n. Common targets: 0.80, 0.90, 0.95.",
      "title": "Power Target"
    },
    "ratio": {
      "default": 1,
      "description": "Allocation ratio n1/n2 for two_sample t-test.",
      "exclusiveMinimum": 0,
      "title": "Ratio",
      "type": "number"
    }
  },
  "required": [
    "effect_size"
  ],
  "title": "PowerCalcIn",
  "type": "object"
}
Output schema 
{
  "description": "Output schema for ``scidex.forge.power_calc``.",
  "properties": {
    "power": {
      "anyOf": [
        {
          "type": "number"
        },
        {
          "type": "null"
        }
      ],
      "default": null,
      "description": "Achieved statistical power (1 - beta).",
      "title": "Power"
    },
    "beta": {
      "anyOf": [
        {
          "type": "number"
        },
        {
          "type": "null"
        }
      ],
      "default": null,
      "description": "Type II error rate (false negative probability).",
      "title": "Beta"
    },
    "required_n_for_80pct": {
      "anyOf": [
        {
          "type": "integer"
        },
        {
          "type": "null"
        }
      ],
      "default": null,
      "description": "Sample size needed to achieve 80% power.",
      "title": "Required N For 80Pct"
    },
    "required_n_for_95pct": {
      "anyOf": [
        {
          "type": "integer"
        },
        {
          "type": "null"
        }
      ],
      "default": null,
      "description": "Sample size needed to achieve 95% power.",
      "title": "Required N For 95Pct"
    },
    "backend": {
      "description": "'scipy' if scipy.stats available, 'approx' if pure-Python fallback.",
      "title": "Backend",
      "type": "string"
    },
    "notes": {
      "default": "",
      "description": "Warning or informational message.",
      "title": "Notes",
      "type": "string"
    }
  },
  "required": [
    "backend"
  ],
  "title": "PowerCalcOut",
  "type": "object"
}

curl snippet

Replace $SCIDEX_JWT with a valid bearer token. Read verbs are usually accessible without auth in dev; production requires a JWT.

curl -sS -X POST '/api/scidex/forge/power_calc' \
  -H 'authorization: Bearer $SCIDEX_JWT' \
  -H 'content-type: application/json' \
  -d '{
  "effect_size": 0
}'

Discussion

Posting anonymously. Sign in for attribution.

No comments yet — be the first.