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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

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  1. Flemingo

    Marsh or Willow Tit (Europe, determining)

    Its not a case of how many willow tits are misidentified its a case of how many birds identified as wilow tits are actually willow tits. Its the difference between sensitivity, specificity of a test and positive /negative predictive values. The former are independant of relative population...
  2. Flemingo

    Marsh or Willow Tit (Europe, determining)

    Distinguishing features that are less than 100% accurate are of little concern if both species are almost equally abundant. Unfortunately than can become significant if one species is much rarer. Lets presume Willow tits are only 10% as abundant as marsh tits in a given area. Lets look at a...