healthyverse_tsa

Time Series Analysis and Nested Modeling of the Healthyverse Packages

Steven P. Sanderson II, MPH - Date: 18 April, 2025

This analysis follows a Nested Modeltime Workflow.

Get Data

glimpse(downloads_tbl)
## Rows: 137,359
## Columns: 11
## $ date      <date> 2020-11-23, 2020-11-23, 2020-11-23, 2020-11-23, 2020-11-23,…
## $ time      <Period> 15H 36M 55S, 11H 26M 39S, 23H 34M 44S, 18H 39M 32S, 9H 0M…
## $ date_time <dttm> 2020-11-23 15:36:55, 2020-11-23 11:26:39, 2020-11-23 23:34:…
## $ size      <int> 4858294, 4858294, 4858301, 4858295, 361, 4863722, 4864794, 4…
## $ r_version <chr> NA, "4.0.3", "3.5.3", "3.5.2", NA, NA, NA, NA, NA, NA, NA, N…
## $ r_arch    <chr> NA, "x86_64", "x86_64", "x86_64", NA, NA, NA, NA, NA, NA, NA…
## $ r_os      <chr> NA, "mingw32", "mingw32", "linux-gnu", NA, NA, NA, NA, NA, N…
## $ package   <chr> "healthyR.data", "healthyR.data", "healthyR.data", "healthyR…
## $ version   <chr> "1.0.0", "1.0.0", "1.0.0", "1.0.0", "1.0.0", "1.0.0", "1.0.0…
## $ country   <chr> "US", "US", "US", "GB", "US", "US", "DE", "HK", "JP", "US", …
## $ ip_id     <int> 2069, 2804, 78827, 27595, 90474, 90474, 42435, 74, 7655, 638…

The last day in the data set is 2025-04-16 23:58:30, the file was birthed on: 2024-08-07 07:35:44, and at report knit time is -6060.38 hours old. Happy analyzing!

Now that we have our data lets take a look at it using the skimr package.

skim(downloads_tbl)
   
Name downloads_tbl
Number of rows 137359
Number of columns 11
_______________________  
Column type frequency:  
character 6
Date 1
numeric 2
POSIXct 1
Timespan 1
________________________  
Group variables None

Data summary

Variable type: character

skim_variable n_missing complete_rate min max empty n_unique whitespace
r_version 98865 0.28 5 5 0 46 0
r_arch 98865 0.28 3 7 0 5 0
r_os 98865 0.28 7 15 0 21 0
package 0 1.00 7 13 0 8 0
version 0 1.00 5 17 0 60 0
country 11571 0.92 2 2 0 163 0

Variable type: Date

skim_variable n_missing complete_rate min max median n_unique
date 0 1 2020-11-23 2025-04-16 2023-06-02 1606

Variable type: numeric

skim_variable n_missing complete_rate mean sd p0 p25 p50 p75 p100 hist
size 0 1 1135594.72 1522675.63 355 14701 274998 2367774 5677952 ▇▁▂▁▁
ip_id 0 1 10375.55 18408.15 1 303 3064 11721 209747 ▇▁▁▁▁

Variable type: POSIXct

skim_variable n_missing complete_rate min max median n_unique
date_time 0 1 2020-11-23 09:00:41 2025-04-16 23:58:30 2023-06-02 22:32:54 83632

Variable type: Timespan

skim_variable n_missing complete_rate min max median n_unique
time 0 1 0 59 12H 7M 29S 60

We can see that the following columns are missing a lot of data and for us are most likely not useful anyways, so we will drop them c(r_version, r_arch, r_os)

Plots

Now lets take a look at a time-series plot of the total daily downloads by package. We will use a log scale and place a vertical line at each version release for each package.

Now lets take a look at some time series decomposition graphs.

Feature Engineering

Now that we have our basic data and a shot of what it looks like, let’s add some features to our data which can be very helpful in modeling. Lets start by making a tibble that is aggregated by the day and package, as we are going to be interested in forecasting the next 4 weeks or 28 days for each package. First lets get our base data.

## 
## Call:
## stats::lm(formula = .formula, data = df)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -147.98  -35.49  -10.57   26.70  813.18 
## 
## Coefficients:
##                                                      Estimate Std. Error
## (Intercept)                                        -1.895e+02  7.263e+01
## date                                                1.149e-02  3.853e-03
## lag(value, 1)                                       1.063e-01  2.473e-02
## lag(value, 7)                                       9.931e-02  2.568e-02
## lag(value, 14)                                      9.637e-02  2.571e-02
## lag(value, 21)                                      6.487e-02  2.586e-02
## lag(value, 28)                                      6.390e-02  2.575e-02
## lag(value, 35)                                      6.948e-02  2.581e-02
## lag(value, 42)                                      4.951e-02  2.591e-02
## lag(value, 49)                                      7.016e-02  2.575e-02
## month(date, label = TRUE).L                        -1.041e+01  5.140e+00
## month(date, label = TRUE).Q                         2.583e+00  5.201e+00
## month(date, label = TRUE).C                        -1.209e+01  5.214e+00
## month(date, label = TRUE)^4                        -6.676e+00  5.199e+00
## month(date, label = TRUE)^5                        -1.245e+01  5.206e+00
## month(date, label = TRUE)^6                        -2.807e+00  5.267e+00
## month(date, label = TRUE)^7                        -6.292e+00  5.169e+00
## month(date, label = TRUE)^8                        -4.673e+00  5.176e+00
## month(date, label = TRUE)^9                         5.750e+00  5.194e+00
## month(date, label = TRUE)^10                        4.235e+00  5.271e+00
## month(date, label = TRUE)^11                       -5.741e+00  5.340e+00
## fourier_vec(date, type = "sin", K = 1, period = 7) -1.160e+01  2.384e+00
## fourier_vec(date, type = "cos", K = 1, period = 7)  7.951e+00  2.512e+00
##                                                    t value Pr(>|t|)    
## (Intercept)                                         -2.609 0.009159 ** 
## date                                                 2.982 0.002912 ** 
## lag(value, 1)                                        4.298 1.83e-05 ***
## lag(value, 7)                                        3.868 0.000114 ***
## lag(value, 14)                                       3.748 0.000184 ***
## lag(value, 21)                                       2.508 0.012230 *  
## lag(value, 28)                                       2.482 0.013165 *  
## lag(value, 35)                                       2.692 0.007183 ** 
## lag(value, 42)                                       1.911 0.056199 .  
## lag(value, 49)                                       2.725 0.006510 ** 
## month(date, label = TRUE).L                         -2.025 0.043013 *  
## month(date, label = TRUE).Q                          0.497 0.619534    
## month(date, label = TRUE).C                         -2.318 0.020586 *  
## month(date, label = TRUE)^4                         -1.284 0.199339    
## month(date, label = TRUE)^5                         -2.391 0.016916 *  
## month(date, label = TRUE)^6                         -0.533 0.594128    
## month(date, label = TRUE)^7                         -1.217 0.223750    
## month(date, label = TRUE)^8                         -0.903 0.366772    
## month(date, label = TRUE)^9                          1.107 0.268387    
## month(date, label = TRUE)^10                         0.804 0.421789    
## month(date, label = TRUE)^11                        -1.075 0.282498    
## fourier_vec(date, type = "sin", K = 1, period = 7)  -4.865 1.26e-06 ***
## fourier_vec(date, type = "cos", K = 1, period = 7)   3.165 0.001583 ** 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 58.78 on 1534 degrees of freedom
##   (49 observations deleted due to missingness)
## Multiple R-squared:  0.2479, Adjusted R-squared:  0.2371 
## F-statistic: 22.98 on 22 and 1534 DF,  p-value: < 2.2e-16

NNS Forecasting

This is something I have been wanting to try for a while. The NNS package is a great package for forecasting time series data.

NNS GitHub

library(NNS)

data_list <- base_data |>
    select(package, value) |>
    group_split(package)

data_list |>
    imap(
        \(x, idx) {
            obj <- x
            x <- obj |> pull(value) |> tail(7*52)
            train_set_size <- length(x) - 56
            pkg <- obj |> pluck(1) |> unique()
            sf <- NNS.seas(x, modulo = 7, plot = FALSE)$periods
            
            cat(paste0("Package: ", pkg, "\n"))
            NNS.ARMA.optim(
                variable = x,
                h = 28,
                training.set = train_set_size,
                #seasonal.factor = seq(12, 60, 7),
                seasonal.factor = sf,
                pred.int = 0.95,
                plot = TRUE
            )
            title(
                sub = paste0("\n",
                             "Package: ", pkg, " - NNS Optimization")
            )
        }
    )
## Package: healthyR
## [1] "CURRNET METHOD: lin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 63 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 2.96421994505375"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 63, 91 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 2.50730127755907"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 63, 91, 70 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 2.44827147523047"
## [1] "BEST method = 'lin', seasonal.factor = c( 63, 91, 70 )"
## [1] "BEST lin OBJECTIVE FUNCTION = 2.44827147523047"
## [1] "CURRNET METHOD: nonlin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 63, 91, 70 ) ...)"
## [1] "CURRENT nonlin OBJECTIVE FUNCTION = 4.22298939920344"
## [1] "BEST method = 'nonlin' PATH MEMBER = c( 63, 91, 70 )"
## [1] "BEST nonlin OBJECTIVE FUNCTION = 4.22298939920344"
## [1] "CURRNET METHOD: both"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 63, 91, 70 ) ...)"
## [1] "CURRENT both OBJECTIVE FUNCTION = 3.14654436267833"
## [1] "BEST method = 'both' PATH MEMBER = c( 63, 91, 70 )"
## [1] "BEST both OBJECTIVE FUNCTION = 3.14654436267833"

## Package: healthyR.ai
## [1] "CURRNET METHOD: lin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 63 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 2.44321524718395"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 63, 98 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 1.89689991368037"
## [1] "BEST method = 'lin', seasonal.factor = c( 63, 98 )"
## [1] "BEST lin OBJECTIVE FUNCTION = 1.89689991368037"
## [1] "CURRNET METHOD: nonlin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 63, 98 ) ...)"
## [1] "CURRENT nonlin OBJECTIVE FUNCTION = 2.28585135198188"
## [1] "BEST method = 'nonlin' PATH MEMBER = c( 63, 98 )"
## [1] "BEST nonlin OBJECTIVE FUNCTION = 2.28585135198188"
## [1] "CURRNET METHOD: both"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 63, 98 ) ...)"
## [1] "CURRENT both OBJECTIVE FUNCTION = 1.94739191680271"
## [1] "BEST method = 'both' PATH MEMBER = c( 63, 98 )"
## [1] "BEST both OBJECTIVE FUNCTION = 1.94739191680271"

## Package: healthyR.data
## [1] "CURRNET METHOD: lin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 98 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 2.10106552447094"
## [1] "BEST method = 'lin', seasonal.factor = c( 98 )"
## [1] "BEST lin OBJECTIVE FUNCTION = 2.10106552447094"
## [1] "CURRNET METHOD: nonlin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 98 ) ...)"
## [1] "CURRENT nonlin OBJECTIVE FUNCTION = 2.46760759916857"
## [1] "BEST method = 'nonlin' PATH MEMBER = c( 98 )"
## [1] "BEST nonlin OBJECTIVE FUNCTION = 2.46760759916857"
## [1] "CURRNET METHOD: both"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 98 ) ...)"
## [1] "CURRENT both OBJECTIVE FUNCTION = 2.14131028554055"
## [1] "BEST method = 'both' PATH MEMBER = c( 98 )"
## [1] "BEST both OBJECTIVE FUNCTION = 2.14131028554055"

## Package: healthyR.ts
## [1] "CURRNET METHOD: lin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 63 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 2.40087402589534"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 63, 98 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 2.0101134594531"
## [1] "BEST method = 'lin', seasonal.factor = c( 63, 98 )"
## [1] "BEST lin OBJECTIVE FUNCTION = 2.0101134594531"
## [1] "CURRNET METHOD: nonlin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 63, 98 ) ...)"
## [1] "CURRENT nonlin OBJECTIVE FUNCTION = 3.19364655255016"
## [1] "BEST method = 'nonlin' PATH MEMBER = c( 63, 98 )"
## [1] "BEST nonlin OBJECTIVE FUNCTION = 3.19364655255016"
## [1] "CURRNET METHOD: both"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 63, 98 ) ...)"
## [1] "CURRENT both OBJECTIVE FUNCTION = 2.47653323791533"
## [1] "BEST method = 'both' PATH MEMBER = c( 63, 98 )"
## [1] "BEST both OBJECTIVE FUNCTION = 2.47653323791533"

## Package: healthyverse
## [1] "CURRNET METHOD: lin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 91 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 3.80463938202456"
## [1] "BEST method = 'lin', seasonal.factor = c( 91 )"
## [1] "BEST lin OBJECTIVE FUNCTION = 3.80463938202456"
## [1] "CURRNET METHOD: nonlin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 91 ) ...)"
## [1] "CURRENT nonlin OBJECTIVE FUNCTION = 5.38626154815699"
## [1] "BEST method = 'nonlin' PATH MEMBER = c( 91 )"
## [1] "BEST nonlin OBJECTIVE FUNCTION = 5.38626154815699"
## [1] "CURRNET METHOD: both"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 91 ) ...)"
## [1] "CURRENT both OBJECTIVE FUNCTION = 4.34040228738022"
## [1] "BEST method = 'both' PATH MEMBER = c( 91 )"
## [1] "BEST both OBJECTIVE FUNCTION = 4.34040228738022"

## Package: RandomWalker
## [1] "CURRNET METHOD: lin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 42 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 1.8832062859861"
## [1] "BEST method = 'lin', seasonal.factor = c( 42 )"
## [1] "BEST lin OBJECTIVE FUNCTION = 1.8832062859861"
## [1] "CURRNET METHOD: nonlin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 42 ) ...)"
## [1] "CURRENT nonlin OBJECTIVE FUNCTION = 2.23924128184997"
## [1] "BEST method = 'nonlin' PATH MEMBER = c( 42 )"
## [1] "BEST nonlin OBJECTIVE FUNCTION = 2.23924128184997"
## [1] "CURRNET METHOD: both"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 42 ) ...)"
## [1] "CURRENT both OBJECTIVE FUNCTION = 1.82202040181459"
## [1] "BEST method = 'both' PATH MEMBER = c( 42 )"
## [1] "BEST both OBJECTIVE FUNCTION = 1.82202040181459"

## Package: tidyAML
## [1] "CURRNET METHOD: lin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 28 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 4.17654966954133"
## [1] "BEST method = 'lin', seasonal.factor = c( 28 )"
## [1] "BEST lin OBJECTIVE FUNCTION = 4.17654966954133"
## [1] "CURRNET METHOD: nonlin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 28 ) ...)"
## [1] "CURRENT nonlin OBJECTIVE FUNCTION = 2.7576357499475"
## [1] "BEST method = 'nonlin' PATH MEMBER = c( 28 )"
## [1] "BEST nonlin OBJECTIVE FUNCTION = 2.7576357499475"
## [1] "CURRNET METHOD: both"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 28 ) ...)"
## [1] "CURRENT both OBJECTIVE FUNCTION = 2.6564814874381"
## [1] "BEST method = 'both' PATH MEMBER = c( 28 )"
## [1] "BEST both OBJECTIVE FUNCTION = 2.6564814874381"

## Package: TidyDensity
## [1] "CURRNET METHOD: lin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 63 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 2.91839912048994"
## [1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 63, 77 ) ...)"
## [1] "CURRENT lin OBJECTIVE FUNCTION = 2.89641011559762"
## [1] "BEST method = 'lin', seasonal.factor = c( 63, 77 )"
## [1] "BEST lin OBJECTIVE FUNCTION = 2.89641011559762"
## [1] "CURRNET METHOD: nonlin"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 63, 77 ) ...)"
## [1] "CURRENT nonlin OBJECTIVE FUNCTION = 3.72253043687994"
## [1] "BEST method = 'nonlin' PATH MEMBER = c( 63, 77 )"
## [1] "BEST nonlin OBJECTIVE FUNCTION = 3.72253043687994"
## [1] "CURRNET METHOD: both"
## [1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
## [1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 63, 77 ) ...)"
## [1] "CURRENT both OBJECTIVE FUNCTION = 3.13079196938131"
## [1] "BEST method = 'both' PATH MEMBER = c( 63, 77 )"
## [1] "BEST both OBJECTIVE FUNCTION = 3.13079196938131"

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Pre-Processing

Now we are going to do some basic pre-processing.

data_padded_tbl <- base_data %>%
  pad_by_time(
    .date_var  = date,
    .pad_value = 0
  )

# Get log interval and standardization parameters
log_params  <- liv(data_padded_tbl$value, limit_lower = 0, offset = 1, silent = TRUE)
limit_lower <- log_params$limit_lower
limit_upper <- log_params$limit_upper
offset      <- log_params$offset

data_liv_tbl <- data_padded_tbl %>%
  # Get log interval transform
  mutate(value_trans = liv(value, limit_lower = 0, offset = 1, silent = TRUE)$log_scaled)

# Get Standardization Params
std_params <- standard_vec(data_liv_tbl$value_trans, silent = TRUE)
std_mean   <- std_params$mean
std_sd     <- std_params$sd

data_transformed_tbl <- data_liv_tbl %>%
  # get standardization
  mutate(value_trans = standard_vec(value_trans, silent = TRUE)$standard_scaled) %>%
  select(-value)

Since this is panel data we can follow one of two different modeling strategies. We can search for a global model in the panel data or we can use nested forecasting finding the best model for each of the time series. Since we only have 5 panels, we will use nested forecasting.

To do this we will use the nest_timeseries and split_nested_timeseries functions to create a nested tibble.

horizon <- 4*7

nested_data_tbl <- data_transformed_tbl %>%
    
    # 1. Extending: We'll predict n days into the future.
    extend_timeseries(
        .id_var        = package,
        .date_var      = date,
        .length_future = horizon
    ) %>%
    
    # 2. Nesting: We'll group by id, and create a future dataset
    #    that forecasts n days of extended data and
    #    an actual dataset that contains n*2 days
    nest_timeseries(
        .id_var        = package,
        .length_future = horizon
        #.length_actual = horizon*2
    ) %>%
    
   # 3. Splitting: We'll take the actual data and create splits
   #    for accuracy and confidence interval estimation of n das (test)
   #    and the rest is training data
    split_nested_timeseries(
        .length_test = horizon
    )

nested_data_tbl
## # A tibble: 8 × 4
##   package       .actual_data         .future_data      .splits          
##   <fct>         <list>               <list>            <list>           
## 1 healthyR.data <tibble [1,599 × 2]> <tibble [28 × 2]> <split [1571|28]>
## 2 healthyR      <tibble [1,592 × 2]> <tibble [28 × 2]> <split [1564|28]>
## 3 healthyR.ts   <tibble [1,536 × 2]> <tibble [28 × 2]> <split [1508|28]>
## 4 healthyverse  <tibble [1,507 × 2]> <tibble [28 × 2]> <split [1479|28]>
## 5 healthyR.ai   <tibble [1,331 × 2]> <tibble [28 × 2]> <split [1303|28]>
## 6 TidyDensity   <tibble [1,182 × 2]> <tibble [28 × 2]> <split [1154|28]>
## 7 tidyAML       <tibble [790 × 2]>   <tibble [28 × 2]> <split [762|28]> 
## 8 RandomWalker  <tibble [212 × 2]>   <tibble [28 × 2]> <split [184|28]>

Now it is time to make some recipes and models using the modeltime workflow.

Modeltime Workflow

Recipe Object

recipe_base <- recipe(
  value_trans ~ date
  , data = extract_nested_test_split(nested_data_tbl)
  )

recipe_base

recipe_date <- recipe_base %>%
    step_mutate(date = as.numeric(date))

Models

# Models ------------------------------------------------------------------

# Auto ARIMA --------------------------------------------------------------

model_spec_arima_no_boost <- arima_reg() %>%
  set_engine(engine = "auto_arima")

wflw_auto_arima <- workflow() %>%
  add_recipe(recipe = recipe_base) %>%
  add_model(model_spec_arima_no_boost)

# NNETAR ------------------------------------------------------------------

model_spec_nnetar <- nnetar_reg(
  mode              = "regression"
  , seasonal_period = "auto"
) %>%
  set_engine("nnetar")

wflw_nnetar <- workflow() %>%
  add_recipe(recipe = recipe_base) %>%
  add_model(model_spec_nnetar)

# TSLM --------------------------------------------------------------------

model_spec_lm <- linear_reg() %>%
  set_engine("lm")

wflw_lm <- workflow() %>%
  add_recipe(recipe = recipe_base) %>%
  add_model(model_spec_lm)

# MARS --------------------------------------------------------------------

model_spec_mars <- mars(mode = "regression") %>%
  set_engine("earth")

wflw_mars <- workflow() %>%
  add_recipe(recipe = recipe_base) %>%
  add_model(model_spec_mars)

Nested Modeltime Tables

nested_modeltime_tbl <- modeltime_nested_fit(
  # Nested Data
  nested_data = nested_data_tbl,
   control = control_nested_fit(
     verbose = TRUE,
     allow_par = FALSE
   ),
  # Add workflows
  wflw_auto_arima,
  wflw_lm,
  wflw_mars,
  wflw_nnetar
)
nested_modeltime_tbl <- nested_modeltime_tbl[!is.na(nested_modeltime_tbl$package),]

Model Accuracy

nested_modeltime_tbl %>%
  extract_nested_test_accuracy() %>%
  filter(!is.na(package)) %>%
  knitr::kable()
package .model_id .model_desc .type mae mape mase smape rmse rsq
healthyR.data 1 ARIMA Test 0.8166529 175.01566 0.6519883 163.7885 0.9436430 0.1099733
healthyR.data 2 LM Test 0.7797320 169.69811 0.6225119 146.5980 0.9057676 0.0493791
healthyR.data 3 EARTH Test 1.0496093 330.43926 0.8379729 131.9468 1.2606270 0.0493791
healthyR.data 4 NNAR Test 0.7440144 116.48452 0.5939962 171.9089 0.9355045 0.0000001
healthyR 1 ARIMA Test 0.7388047 104.16298 0.7297873 178.2227 0.9099680 0.0256899
healthyR 2 LM Test 0.7115738 97.97049 0.7028887 185.6999 0.8742374 0.0715654
healthyR 3 EARTH Test 0.7111615 97.21340 0.7024814 177.0310 0.8729731 0.0715654
healthyR 4 NNAR Test 0.7476649 100.15380 0.7385394 158.6677 0.9256955 0.0473272
healthyR.ts 1 ARIMA Test 0.9143378 273.40720 0.7268053 148.3628 1.1273960 0.0455431
healthyR.ts 2 LM Test 0.9345655 326.40447 0.7428843 141.1867 1.1680833 0.0455431
healthyR.ts 3 EARTH Test 0.9335866 322.95318 0.7421061 141.8001 1.1648705 NA
healthyR.ts 4 NNAR Test 0.9431758 166.34090 0.7497286 179.3385 1.1791870 0.0337781
healthyverse 1 ARIMA Test 0.6692285 351.45408 0.6858813 111.7667 0.8381570 0.0154100
healthyverse 2 LM Test 0.6698987 432.19256 0.6865681 105.4821 0.8229659 0.0025692
healthyverse 3 EARTH Test 0.6511266 263.86872 0.6673289 116.1471 0.8487658 0.0025692
healthyverse 4 NNAR Test 0.6677176 247.36087 0.6843327 122.0862 0.8722359 0.0139842
healthyR.ai 1 ARIMA Test 0.7254637 148.82572 0.7240198 179.4298 0.9424998 0.0405568
healthyR.ai 2 LM Test 0.6664376 146.02753 0.6651112 146.8749 0.8685641 0.0359816
healthyR.ai 3 EARTH Test 0.6717265 123.98120 0.6703895 153.3813 0.8802402 0.0359816
healthyR.ai 4 NNAR Test 0.7896146 173.76226 0.7880430 161.5622 1.0330173 0.1332527
TidyDensity 1 ARIMA Test 0.6205283 308.70846 0.6902220 111.5305 0.7536063 0.0569331
TidyDensity 2 LM Test 0.6419715 367.50284 0.7140734 102.3069 0.8171988 0.0977793
TidyDensity 3 EARTH Test 0.6171700 269.02775 0.6864865 109.4917 0.7734796 0.0977793
TidyDensity 4 NNAR Test 0.6868838 253.30594 0.7640300 145.4068 0.8267306 0.0083488
tidyAML 1 ARIMA Test 0.6427715 317.61615 0.8458465 101.6648 0.7999587 0.0377784
tidyAML 2 LM Test 0.6540296 310.78721 0.8606616 103.8010 0.8058125 0.0343169
tidyAML 3 EARTH Test 0.6803634 337.60786 0.8953151 104.3609 0.8313325 0.0343169
tidyAML 4 NNAR Test 0.6408142 294.51774 0.8432709 104.3341 0.7879498 0.0024578
RandomWalker 1 ARIMA Test 1.2134277 116.25743 0.5920482 173.2953 1.4373721 0.0021978
RandomWalker 2 LM Test 1.2237908 98.82794 0.5971046 193.1199 1.4389783 0.0879682
RandomWalker 3 EARTH Test 1.2085690 110.11240 0.5896776 170.2913 1.4376996 NA
RandomWalker 4 NNAR Test 1.4349838 280.29409 0.7001486 156.5642 1.6259132 0.0000682

Plot Models

nested_modeltime_tbl %>%
  extract_nested_test_forecast() %>%
  group_by(package) %>%
  plot_modeltime_forecast(
    .interactive = FALSE,
    .conf_interval_show  = FALSE,
    .facet_scales = "free"
  ) +
  theme_minimal() +
  theme(legend.position = "bottom")

Best Model

best_nested_modeltime_tbl <- nested_modeltime_tbl %>%
  modeltime_nested_select_best(
    metric = "rmse",
    minimize = TRUE,
    filter_test_forecasts = TRUE
  )

best_nested_modeltime_tbl %>%
  extract_nested_best_model_report()
## # Nested Modeltime Table
## 

## # A tibble: 8 × 10
##   package      .model_id .model_desc .type   mae  mape  mase smape  rmse     rsq
##   <fct>            <int> <chr>       <chr> <dbl> <dbl> <dbl> <dbl> <dbl>   <dbl>
## 1 healthyR.da…         2 LM          Test  0.780 170.  0.623  147. 0.906 0.0494 
## 2 healthyR             3 EARTH       Test  0.711  97.2 0.702  177. 0.873 0.0716 
## 3 healthyR.ts          1 ARIMA       Test  0.914 273.  0.727  148. 1.13  0.0455 
## 4 healthyverse         2 LM          Test  0.670 432.  0.687  105. 0.823 0.00257
## 5 healthyR.ai          2 LM          Test  0.666 146.  0.665  147. 0.869 0.0360 
## 6 TidyDensity          1 ARIMA       Test  0.621 309.  0.690  112. 0.754 0.0569 
## 7 tidyAML              4 NNAR        Test  0.641 295.  0.843  104. 0.788 0.00246
## 8 RandomWalker         1 ARIMA       Test  1.21  116.  0.592  173. 1.44  0.00220
best_nested_modeltime_tbl %>%
  extract_nested_test_forecast() %>%
  #filter(!is.na(.model_id)) %>%
  group_by(package) %>%
  plot_modeltime_forecast(
    .interactive = FALSE,
    .conf_interval_alpha = 0.2,
    .facet_scales = "free"
  ) +
  theme_minimal() +
  theme(legend.position = "bottom")

Refitting and Future Forecast

Now that we have the best models, we can make our future forecasts.

nested_modeltime_refit_tbl <- best_nested_modeltime_tbl %>%
    modeltime_nested_refit(
        control = control_nested_refit(verbose = TRUE)
    )
nested_modeltime_refit_tbl
## # Nested Modeltime Table
## 

## # A tibble: 8 × 5
##   package       .actual_data .future_data .splits           .modeltime_tables 
##   <fct>         <list>       <list>       <list>            <list>            
## 1 healthyR.data <tibble>     <tibble>     <split [1571|28]> <mdl_tm_t [1 × 5]>
## 2 healthyR      <tibble>     <tibble>     <split [1564|28]> <mdl_tm_t [1 × 5]>
## 3 healthyR.ts   <tibble>     <tibble>     <split [1508|28]> <mdl_tm_t [1 × 5]>
## 4 healthyverse  <tibble>     <tibble>     <split [1479|28]> <mdl_tm_t [1 × 5]>
## 5 healthyR.ai   <tibble>     <tibble>     <split [1303|28]> <mdl_tm_t [1 × 5]>
## 6 TidyDensity   <tibble>     <tibble>     <split [1154|28]> <mdl_tm_t [1 × 5]>
## 7 tidyAML       <tibble>     <tibble>     <split [762|28]>  <mdl_tm_t [1 × 5]>
## 8 RandomWalker  <tibble>     <tibble>     <split [184|28]>  <mdl_tm_t [1 × 5]>
nested_modeltime_refit_tbl %>%
  extract_nested_future_forecast() %>%
  mutate(across(.value:.conf_hi, .fns = ~ standard_inv_vec(
    x    = .,
    mean = std_mean,
    sd   = std_sd
  )$standard_inverse_value)) %>%
  mutate(across(.value:.conf_hi, .fns = ~ liiv(
    x = .,
    limit_lower = limit_lower,
    limit_upper = limit_upper,
    offset      = offset
  )$rescaled_v)) %>%
  group_by(package) %>%
  plot_modeltime_forecast(
    .interactive = FALSE,
    .conf_interval_alpha = 0.2,
    .facet_scales = "free"
  ) +
  theme_minimal() +
  theme(legend.position = "bottom")