Matches in SemOpenAlex for { <https://semopenalex.org/work/W1987362922> ?p ?o ?g. }
- W1987362922 endingPage "780" @default.
- W1987362922 startingPage "774" @default.
- W1987362922 abstract "We apply instance-based machine learning in the form of a k-nearest neighbor algorithm to the task of estimating photometric redshifts for 55,746 objects spectroscopically classified as quasars in the Fifth Data Release of the Sloan Digital Sky Survey. We compare the results obtained to those from an empirical color-redshift relation (CZR). In contrast to previously published results using CZRs, we find that the instance-based photometric redshifts are assigned with no regions of catastrophic failure. Remaining outliers are simply scattered about the ideal relation, in a similar manner to the pattern seen in the optical for normal galaxies at redshifts z < ~1. The instance-based algorithm is trained on a representative sample of the data and pseudo-blind-tested on the remaining unseen data. The variance between the photometric and spectroscopic redshifts is sigma^2 = 0.123 +/- 0.002 (compared to sigma^2 = 0.265 +/- 0.006 for the CZR), and 54.9 +/- 0.7%, 73.3 +/- 0.6%, and 80.7 +/- 0.3% of the objects are within delta z < 0.1, 0.2, and 0.3 respectively. We also match our sample to the Second Data Release of the Galaxy Evolution Explorer legacy data and the resulting 7,642 objects show a further improvement, giving a variance of sigma^2 = 0.054 +/- 0.005, and 70.8 +/- 1.2%, 85.8 +/- 1.0%, and 90.8 +/- 0.7% of objects within delta z < 0.1, 0.2, and 0.3. We show that the improvement is indeed due to the extra information provided by GALEX, by training on the same dataset using purely SDSS photometry, which has a variance of sigma^2 = 0.090 +/- 0.007. Each set of results represents a realistic standard for application to further datasets for which the spectra are representative." @default.
- W1987362922 created "2016-06-24" @default.
- W1987362922 creator A5036640710 @default.
- W1987362922 creator A5043454829 @default.
- W1987362922 creator A5054388255 @default.
- W1987362922 creator A5058172787 @default.
- W1987362922 creator A5066643515 @default.
- W1987362922 creator A5078172733 @default.
- W1987362922 creator A5085763615 @default.
- W1987362922 date "2007-07-10" @default.
- W1987362922 modified "2023-10-17" @default.
- W1987362922 title "Robust Machine Learning Applied to Astronomical Data Sets. II. Quantifying Photometric Redshifts for Quasars Using Instance‐based Learning" @default.
- W1987362922 cites W1480376833 @default.
- W1987362922 cites W18414812 @default.
- W1987362922 cites W1970531442 @default.
- W1987362922 cites W1972053729 @default.
- W1987362922 cites W1972381235 @default.
- W1987362922 cites W1978622282 @default.
- W1987362922 cites W1989353568 @default.
- W1987362922 cites W1996537612 @default.
- W1987362922 cites W2005750050 @default.
- W1987362922 cites W2010677644 @default.
- W1987362922 cites W2031749817 @default.
- W1987362922 cites W2032744495 @default.
- W1987362922 cites W2034133576 @default.
- W1987362922 cites W2036914160 @default.
- W1987362922 cites W2049764493 @default.
- W1987362922 cites W2051291450 @default.
- W1987362922 cites W2058635514 @default.
- W1987362922 cites W2059963108 @default.
- W1987362922 cites W2060792137 @default.
- W1987362922 cites W2064308618 @default.
- W1987362922 cites W2066773429 @default.
- W1987362922 cites W2080691528 @default.
- W1987362922 cites W2092569692 @default.
- W1987362922 cites W2103067535 @default.
- W1987362922 cites W2109510044 @default.
- W1987362922 cites W2111817932 @default.
- W1987362922 cites W2117431169 @default.
- W1987362922 cites W2122111042 @default.
- W1987362922 cites W2128515757 @default.
- W1987362922 cites W2130908251 @default.
- W1987362922 cites W2132711591 @default.
- W1987362922 cites W2136404024 @default.
- W1987362922 cites W2140398358 @default.
- W1987362922 cites W2142220522 @default.
- W1987362922 cites W2146103050 @default.
- W1987362922 cites W2147526948 @default.
- W1987362922 cites W2150195330 @default.
- W1987362922 cites W2157917411 @default.
- W1987362922 cites W2163859725 @default.
- W1987362922 cites W2167635287 @default.
- W1987362922 cites W2591733255 @default.
- W1987362922 cites W2950912493 @default.
- W1987362922 cites W2952061305 @default.
- W1987362922 cites W3099186397 @default.
- W1987362922 cites W3099270657 @default.
- W1987362922 cites W3102738652 @default.
- W1987362922 cites W3103614349 @default.
- W1987362922 cites W3104300173 @default.
- W1987362922 cites W3123261968 @default.
- W1987362922 cites W3126126471 @default.
- W1987362922 doi "https://doi.org/10.1086/518362" @default.
- W1987362922 hasPublicationYear "2007" @default.
- W1987362922 type Work @default.
- W1987362922 sameAs 1987362922 @default.
- W1987362922 citedByCount "48" @default.
- W1987362922 countsByYear W19873629222012 @default.
- W1987362922 countsByYear W19873629222013 @default.
- W1987362922 countsByYear W19873629222014 @default.
- W1987362922 countsByYear W19873629222015 @default.
- W1987362922 countsByYear W19873629222016 @default.
- W1987362922 countsByYear W19873629222017 @default.
- W1987362922 countsByYear W19873629222018 @default.
- W1987362922 countsByYear W19873629222019 @default.
- W1987362922 countsByYear W19873629222020 @default.
- W1987362922 countsByYear W19873629222021 @default.
- W1987362922 countsByYear W19873629222022 @default.
- W1987362922 countsByYear W19873629222023 @default.
- W1987362922 crossrefType "journal-article" @default.
- W1987362922 hasAuthorship W1987362922A5036640710 @default.
- W1987362922 hasAuthorship W1987362922A5043454829 @default.
- W1987362922 hasAuthorship W1987362922A5054388255 @default.
- W1987362922 hasAuthorship W1987362922A5058172787 @default.
- W1987362922 hasAuthorship W1987362922A5066643515 @default.
- W1987362922 hasAuthorship W1987362922A5078172733 @default.
- W1987362922 hasAuthorship W1987362922A5085763615 @default.
- W1987362922 hasBestOaLocation W19873629221 @default.
- W1987362922 hasConcept C121332964 @default.
- W1987362922 hasConcept C1276947 @default.
- W1987362922 hasConcept C135041427 @default.
- W1987362922 hasConcept C139809296 @default.
- W1987362922 hasConcept C154945302 @default.
- W1987362922 hasConcept C2778049214 @default.
- W1987362922 hasConcept C2779556658 @default.
- W1987362922 hasConcept C2780974285 @default.
- W1987362922 hasConcept C33024259 @default.
- W1987362922 hasConcept C41008148 @default.