Assess Water Quality Trends with Generalized Additive Models
Extract period (seasonal) averages from fitted GAM
Back-transform response variable
Return summary statistics for GAM fits
Fit a generalized additive model to a water quality time series
Extract period (seasonal) metrics from fitted GAM
Fit a mixed meta-analysis regression model of trends
Estimate percent change trends from GAM results for selected time peri...
Get predicted data from fitted GAMs across period of observation
Get predicted data from fitted GAMs across period of observation, ever...
Get prediction matrix for a fitted GAM
Format p-values for show functions
Return summary statistics for smoothers of GAMs
Retrieve summary statistics for seasonal metrics and trend results
Estimate seasonal rates of change based on average estimates for multi...
Transform response variable
Estimate rates of change based on seasonal metrics
Plot period (seasonal) averages from fitted GAM
Plot seasonal metrics and rates of change
Plot percent change trends from GAM results for selected time periods
Plot a 3-d surface of predictions
Plot predictions for GAMs against day of year
Plot predictions for GAMs over time, by season
Plot predictions for GAMs over time series
Plot seasonal rates of change based on average estimates for multiple ...
Plot seasonal rates of change in quarters based on average estimates f...
Plot rates of change based on seasonal metrics
Assess Water Quality Trends for Long-Term Monitoring Data in Estuaries using Generalized Additive Models following Wood (2017) <doi:10.1201/9781315370279> and Error Propagation with Mixed-Effects Meta-Analysis following Sera et al. (2019) <doi:10.1002/sim.8362>. Methods are available for model fitting, assessment of fit, annual and seasonal trend tests, and visualization of results.
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