monitor_performance: Calculate Monitor Prediction Performance

In PWFSLSmoke: Utilities for Working with Air Quality Monitoring Data

Description

This function uses confusion matrix analysis to calculate different measures of predictive performance for every timeseries found in predicted with respect to the observed values found in the single timeseries found in observed.

The requested metric is returned in a dataframe organized with one row per monitor, all available metrics are returned.

Usage

monitor_performance(
  predicted,
  observed,
  t1,
  t2,
  metric = NULL,
  FPCost = 1,
  FNCost = 1
)

Arguments

predicted	ws_monitor object with predicted data
observed	ws_monitor object with observed data
t1	value used to classify predicted measurements
t2	threshold used to classify observed measurements
metric	confusion matrix metric to be used
FPCost	cost associated with false positives (type II error)
FNCost	cost associated with false negatives (type I error)

Value

Dataframe of monitors vs named measure of performance.

See Also

monitor_performanceMap

skill_confusionMatrix

Examples

# Fail gracefully if any resources are not available
try({

library(PWFSLSmoke)

# If daily avg data were the prediciton and Spokane were
# the observed, which WA State monitors had skill?

wa <- airnow_loadAnnual(2017) %>% monitor_subset(stateCodes='WA')
wa_dailyAvg <- monitor_dailyStatistic(wa, mean)
Spokane_dailyAvg <- monitor_subset(wa_dailyAvg, monitorIDs='530630021_01')

threshold <- AQI$breaks_24[4] # Unhealthy
performanceMetrics <- monitor_performance(wa_dailyAvg,
                                          Spokane_dailyAvg,
                                          threshold, threshold)

monitorIDs <- rownames(performanceMetrics)
mask <- performanceMetrics$heidkeSkill &
        !is.na(performanceMetrics$heidkeSkill)

skillfulIDs <- monitorIDs[mask]
skillful <- monitor_subset(wa_dailyAvg, monitorIDs=skillfulIDs)

monitor_leaflet(skillful)

}, silent = FALSE)

PWFSLSmoke documentation built on Nov. 23, 2021, 5:06 p.m.