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rplotpredictionforecasting

Obtaining prediction point estimates and intervals from a forecast with forecast package


I need a way to print the values from a forecast.

I need to print the dark blue line value and, if possible, the values from the grey area in the picture below.

What would be the code to print that value or to print 2019 forecast values?

library(forecast)

timese <- ts(WWWusage, start = c(2008, 1), end = c(2016, 1), frequency = 12)

### Structural Time Series Model 
# Trend likelihood    
fit <- StructTS(timese, "trend")

### Make the plot
plot(forecast(fit, level = c(70, 90)), 
     sub = "Confidence Interval 70% ~ 90% or Determined by user", 
     ylab = "Y Axis Variable",
     main = "Forecast Linear Structural Model @ Trend-Wise",
     ylim = c(0, 400))

Plot


Solution

  • Just store the forecast object and print it:

    fc <- forecast(fit, level = c(70, 90))
    fc
    #          Point Forecast    Lo 70    Hi 70    Lo 90    Hi 90
    # Feb 2016            234 230.3083 237.6917 228.1411 239.8589
    # Mar 2016            240 231.7450 248.2550 226.8991 253.1009
    # Apr 2016            246 232.1868 259.8132 224.0780 267.9220
    # May 2016            252 231.7796 272.2204 219.9095 284.0905
    # Jun 2016            258 230.6214 285.3786 214.5493 301.4507
    # Jul 2016            264 228.7832 299.2168 208.1097 319.8903
    # Aug 2016            270 226.3189 313.6811 200.6767 339.3233
    # Sep 2016            276 223.2716 328.7284 192.3183 359.6817
    # Oct 2016            282 219.6765 344.3235 183.0905 380.9095
    # Nov 2016            288 215.5631 360.4369 173.0402 402.9598
    

    For extracting individual rows, it might be easier to convert this to a data.frame:

    df_fc <- as.data.frame(fc)
    df_fc["Jul 2016", ]
    #          Point Forecast    Lo 70    Hi 70    Lo 90    Hi 90
    # Jul 2016            264 228.7832 299.2168 208.1097 319.8903