Survey selection in observed and intrinsic coordinates
Research context
research method · conditional · As of 2026-10-10
A survey's detected density is the underlying observable distribution multiplied by a selection probability.
Key knowledge
A survey's detected density is the underlying observable distribution multiplied by a selection probability. Poisson likelihood includes both observed events and the expected count integral; translating to physical distance/age/metallicity requires an observation/stellar-population mapping.
Values and equations
λ_obs(v)=S(v) λ_parent(v); log L=sum_j log λ_obs(v_j)-integral λ_obs(v) dv
- v
- Declared observed coordinates
- S
- Selection probability 1
- λ_obs,λ_parent
- Event densities in those coordinates
- v_j
- Observed events
Conditions and scope
- The cited spectroscopic method assumes a suitable complete photometric comparison and declares sky-patch and mixture approximations.
- Overlapping fields require union accounting; dust, selection zeros and correlation can prevent an unbiased inverse weighting.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
seestar: Selection functions for spectroscopic surveys of the Milky Way: Sections 2.2–2.3 and 3: Poisson selection model, intrinsic-coordinate transformation and synthetic checks (selected source body inspected).
2026-10-10 · Bounded source check of the recorded statement and conditions. This does not certify a unique physical model, reproduce the cited study or replace independent branch review.
Entry details
Permanent link to this entry ↗- Record identity
- research-earth-survey-poisson
- Revision
- research.1
- Structured reference record
- Postgraduate & research reference