# polls.karbach.digital – German Federal Election Trend (Monte-Carlo Simulation)

> polls.karbach.digital – German Federal Election Trend (Monte-Carlo Simulation) is a paid API for AI agents from api.polls.karbach.digital, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-28).

Returns current Monte-Carlo simulation results for the German federal election (Bundestagswahl), including party vote-share medians, 95% confidence intervals, and parliament-entry probabilities, updated every 6 hours.

## Facts

- Endpoint: GET https://api.polls.karbach.digital/v1/federal/trend?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-28
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/polls-karbach-digital-german-federal-election-trend-monte-carlo-ea01fc99
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_tYZaJbYrznGGl10TptaFS

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 polls-karbach-digital-german-federal-election-trend-monte-carlo-ea01fc99
```

Example prompt: What's the latest Monte-Carlo forecast for the 2029 German federal election — show me each party's median vote share, confidence interval, and their probability of making it into the Bundestag?

## When to prefer this

Choose this endpoint when you need a probabilistic, Monte-Carlo-based forecast for the German federal election (Bundestagswahl) rather than a raw poll average. It is uniquely suited for questions about confidence intervals, parliament-entry probabilities, and coalition arithmetic. Prefer it over generic news APIs or raw polling aggregators when you need calibrated uncertainty quantification (Leave-One-Out validated, MAE ±1.27 pp). Updated every 6 hours, so suitable for near-real-time political monitoring. Not suitable for state-level (Landtag) elections — sibling endpoints exist for those.

## Known failure modes

- Stale data if the 6-hour update cycle is delayed
- No input schema flexibility (GET with no documented query parameters beyond an empty properties object)
- Missing parties if dawum.de source data is incomplete
- Confidence intervals may be wide (e.g. 19.6–40.4 pp for AfD) reflecting genuine poll variance, not model failure
- Out-of-sample calibration holds ~81% (17/21 values), so rare extreme results may fall outside CI
- HTTP errors if the API is unavailable or payment fails via x402 protocol

## How this service works

Federal polling average today per party with 95 percent band (Bundestag). Use when asked how German parties currently stand nationally. Source-attributed, German data, updated every six hours.

## Output

A JSON object containing an array of German political parties each with their median vote share, poll average, 95% confidence interval bounds, and parliament-entry probability (0–100), plus simulation metadata (model version, number of polls used, number of simulations, temporal decay weighting), data source attribution (dawum.de, ODbL 1.0), and a last-updated timestamp. Also includes a notice clarifying this is scenario analysis, not a prediction or voting recommendation.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {
   "parties": [
    {
     "ci95": [
      19.6,
      40.4
     ],
     "name": "AfD",
     "party": "AfD",
     "median": 28.5,
     "poll_average": 28.5,
     "entry_probability": 100
    },
    {
     "ci95": [
      11.1,
      31.4
     ],
     "name": "Union (CDU/CSU)",
     "party": "CDU/CSU",
     "median": 18.8,
     "poll_average": 18.8,
     "entry_probability": 100
    }
   ],
   "election": "btw-2029"
  },
  "docs": "https://api.polls.karbach.digital/v1/",
  "model": {
   "version": "4.16",
   "polls_used": 5,
   "simulations": 10000,
   "point_estimate": "weighted_poll_avg (Fenster 5, temporal_decay_14d + institute_quality)"
  },
  "notice": "Scenario analysis based on published opinion polls. Not a prediction and not a voting recommendation. Coalitions are arithmetic majorities only, not statemen...",
  "source": {
   "polls": "dawum.de",
   "processing": "polls.karbach.digital (Max Karbach)",
   "polls_license": "ODbL 1.0",
   "polls_license_url": "https://opendatacommons.org/licenses/odbl/1-0/"
  },
  "project": "Ein Projekt von Karbach.Digital (https://karbach.digital)",
  "updated_at": "2026-10-17 18:00:09",
  "uncertainty": "ci95: range that contains the result with 95 percent probability in the simulation. Out of sample in 2026 the band held 17 of 21 values (81 percent)."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/polls-karbach-digital-german-federal-election-trend-monte-carlo-ea01fc99/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.polls.karbach.digital](https://www.zero.xyz/host/api.polls.karbach.digital/llms.txt)