Table 4

Nowcast model responses compared to use of previous day's E. coli concentration (persistence model) during validation in 2012a

SiteModel usedNo. of observationsNo. of exceedancesb% correctSensitivity (%)Specificity (%)
Alum CampersNowcast49391.80.097.8
Persistence38289.50.094.4
Alum NorthNowcast490100.00.0100.0
Persistence380100.00.0100.0
Alum CentralNowcast49191.80.093.8
Persistence38197.40.0100.0
Atwood MainNowcast521365.423.179.5
Persistence411078.050.087.1
Buck Creek NorthNowcast45880.062.583.8
Persistence34764.714.377.8
Buck Creek SouthNowcast46973.955.678.4
Persistence34952.911.168.0
GLSM CampersNowcast48266.7100.065.2
Persistence39292.30.097.3
GLSM EastNowcast48279.20.082.6
Persistence40295.00.097.4
Tappan MainNowcast521076.940.085.7
Persistence42969.033.378.8
  • a Model responses that could be evaluated as improved over those of the persistence model are in bold and shaded.

  • b Number of days the Ohio single-sample bathing water standard of 235 CFU/100 ml was exceeded.