Laura, We report (http://bit.ly/1qMUZt8) a relatively limited comparison of our BLED vs. manual extraction for high-frequency calls.
Here are the relevant methods and results (apologies for the length): We compared automated detections with manually quantified NFCs in a sample of 10-minute recordings to evaluate the effectiveness of our automated detector settings. We selected 12 recordings from each site, with two notable constraints: recordings contained ≥4 warbler or sparrow NFCs (median = 7; maximum = 45) and occurred on separate nights. We again ignored NFCs too weak to assign confidently to warblers or sparrows, or NFCs belonging to other bird families. Thus, we estimated detector efficiency under generally favorable recording conditions and compared efficiency among sites and across a restricted range of ambient noise conditions. ...The noise variable represents the average power (dB) in the 6�C11 kHz frequency range in each 10-minute recording. We found little evidence that the efficiency of our automated detector algorithm [Raven BLED in the 6-11 kHz] varied among sites (likelihood ratio test [LRT]: χ2 = 9.92, df = 7, P = 0.19) or with background noise in relatively low-noise conditions (LRT: χ2= 0.03, df = 1, P = 0.86). The automated detector extracted 55�C60% (95% confidence interval) of flight calls attributable to warblers and sparrows under reasonably good recording conditions. Best, Adam Smith Dept. Natural Resources Science 105 Coastal Institute in Kingston University of Rhode Island Kingston, RI 02881 Phone: 859-559-7172 Fax: 401-874-4561 Date: Thu, 11 Sep 2014 18:00:39 -0700 From: lgo...@alum.mit.edu Subject: [nfc-l] Comparison of Detection Methods To: nf...@list.cornell.edu Folks, I'm wondering if anyone has done a formal (or informal but documented) comparison of flight call detections using different methods. Specifically, I'm interested in comparisons of the Raven Band Limited Energy Detectors vs. Bill Evans' Tseep and Thrush vs. hand browsing. Thanks for any information. Laura Gooch Cleveland Heights, Ohio -- NFC-L List Info: Welcome and Basics Rules and Information Subscribe, Configuration and Leave Archives: The Mail Archive Surfbirds BirdingOnThe.Net Please submit your observations to eBird! -- -- NFC-L List Info: http://www.NortheastBirding.com/NFC_WELCOME http://www.NortheastBirding.com/NFC_RULES http://www.NortheastBirding.com/NFC-L_SubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NFC-L 3) http://birdingonthe.net/mailinglists/NFCL.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
