Scoring on this site: smartphone terms explained

11 terms. Back to the full glossary.

Coverage: The share of a category score's formula (by weight) for which we have data on that phone. A phone needs at least 75% coverage to be ranked in a category, and at least 75% for the overall blend. Below that it is listed but not ranked, and its page shows the coverage. Missing data is shown as not confirmed and is never estimated. Related: Required input, Overall score.
Required input: A specification a category cannot be scored without, such as the main sensor size for the camera score. If a phone lacks a required input, it is not ranked in that category even when everything else is known. Optional inputs only refine the score when present, and a few inputs that makers often leave unstated (for example a telephoto sensor size) count at the middle of their scale when unknown. Each category page on the methodology section lists its required and optional inputs. Related: Coverage, Anchor scale.
Anchor scale: A fixed, published table that maps a specification onto 0 to 100, for example battery capacity or telephoto sensor size. Values between two anchor points are scored on the straight line between them and values beyond the ends get the end score. Because the scales are fixed, a phone's score does not change when other phones are added to the catalogue. Where extra capacity brings diminishing returns the scale is logarithmic. Related: Coverage, Overall score.
Budget score: Where a phone's score sits among the ranked phones in a price band, from 0 to 100. On "under" price lists the budget score is shown next to the national score. It is a percentile within that list, so it can change when phones enter or leave the band, unlike the national score. Related: Overall score, Value score.
Value score: How much better or worse a phone's overall score is than expected for its price: 50 means exactly as good as its price predicts. We fit a price line to the overall scores of phones at similar prices and score each phone as 50 plus 2.5 times its distance above or below that line. A phone needs at least three neighbours priced between two-thirds and one-and-a-half times its own price; otherwise it has no value score. Related: Overall score, Budget score.
Overall score: A weighted blend of the category scores: performance 20%, camera 20%, battery 18%, display 14%, software 10%, charging 8%, durability 6%, video 2% and audio 2%. A phone needs performance, camera and battery scores to get an overall score. The weights follow published Indian buyer-priority surveys and are on the methodology page. They are a judgement, which is why we also test how stable each #1 is when the weights change. Related: Coverage, Close call.
Formula version: The number of the scoring rules in force, changed whenever a score or a list rule changes. Each change is described in the methodology changelog. Weekly and monthly archives are frozen and keep the formula version they were made with, so old rankings are never rewritten. Related: Overall score, Anchor scale.
Close call: A #1 that loses its place when the formula weights are varied by up to 25%, or that leads the next phone by under 2 points. We re-score each list 1,000 times with randomly changed weights. If the winner stays first in at least 70% of runs it is stable; otherwise we say so on the page. A gap under 2 points is called effectively tied. Related: Overall score, Formula version.
Verified: A phone whose key specifications have each been confirmed by an official maker source and an independent one. The key specifications are price, chipset, battery, main camera sensor, IP rating and update policy. Both sources are stored with the phone. No phone is marked verified until every one has both. Related: Pending verification, Two-source rule.
Pending verification: The label on a phone whose figures come from launch coverage and have not yet been checked against the maker's own pages. Pending phones are still ranked. Values we could not confirm are shown as not confirmed, and conflicting reports are left out instead of averaged. Related: Verified, Two-source rule.
Two-source rule: Each key specification needs one official maker source and one independent source before a phone is called verified. Two outlets repeating the same press release should count as one source. Review sites are used for research but not linked from published pages; the links shown are maker pages and independent test labs. Related: Verified, Pending verification.