healthyverse_tsa

Time Series Analysis, Modeling and Forecasting of the Healthyverse

Packages Steven P. Sanderson II, MPH - Date: 2025-12-12

Introduction

This analysis follows a Nested Modeltime Workflow from modeltime along with using the NNS package. I use this to monitor the downloads of all of my packages:

Get Data

glimpse(downloads_tbl)
Rows: 162,689
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 2025-12-10 21:45:18, the file was birthed on: 2022-07-02 23:58:17.511888, and at report knit time is 3.016178^{4} 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 162689
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 119350 0.27 5 7 0 50 0
r_arch 119350 0.27 1 7 0 6 0
r_os 119350 0.27 7 19 0 24 0
package 0 1.00 7 13 0 8 0
version 0 1.00 5 17 0 62 0
country 15259 0.91 2 2 0 166 0

Variable type: Date

skim_variable n_missing complete_rate min max median n_unique
date 0 1 2020-11-23 2025-12-10 2023-11-06 1837

Variable type: numeric

skim_variable n_missing complete_rate mean sd p0 p25 p50 p75 p100 hist
size 0 1 1124236.46 1487771.95 355 27709 310297 2352686 5677952 ▇▁▂▁▁
ip_id 0 1 11326.99 21968.41 1 236 2889 11961 299146 ▇▁▁▁▁

Variable type: POSIXct

skim_variable n_missing complete_rate min max median n_unique
date_time 0 1 2020-11-23 09:00:41 2025-12-10 21:45:18 2023-11-06 02:23:35 102695

Variable type: Timespan

skim_variable n_missing complete_rate min max median n_unique
time 0 1 0 59 12H 6M 41S 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.

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

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Seasonal Diagnostics:

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ACF and PACF Diagnostics:

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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 
-146.39  -36.48  -11.25   27.07  819.98 

Coefficients:
                                                     Estimate Std. Error
(Intercept)                                        -1.818e+02  6.026e+01
date                                                1.115e-02  3.195e-03
lag(value, 1)                                       1.095e-01  2.318e-02
lag(value, 7)                                       8.916e-02  2.388e-02
lag(value, 14)                                      7.577e-02  2.385e-02
lag(value, 21)                                      8.111e-02  2.392e-02
lag(value, 28)                                      6.861e-02  2.383e-02
lag(value, 35)                                      5.499e-02  2.389e-02
lag(value, 42)                                      6.360e-02  2.401e-02
lag(value, 49)                                      6.144e-02  2.391e-02
month(date, label = TRUE).L                        -1.068e+01  5.010e+00
month(date, label = TRUE).Q                         3.918e-01  4.930e+00
month(date, label = TRUE).C                        -1.596e+01  4.960e+00
month(date, label = TRUE)^4                        -6.181e+00  4.937e+00
month(date, label = TRUE)^5                        -6.748e+00  4.894e+00
month(date, label = TRUE)^6                         1.218e+00  4.906e+00
month(date, label = TRUE)^7                        -4.515e+00  4.842e+00
month(date, label = TRUE)^8                        -4.035e+00  4.815e+00
month(date, label = TRUE)^9                         2.764e+00  4.828e+00
month(date, label = TRUE)^10                        9.390e-01  4.845e+00
month(date, label = TRUE)^11                       -4.086e+00  4.831e+00
fourier_vec(date, type = "sin", K = 1, period = 7) -1.129e+01  2.210e+00
fourier_vec(date, type = "cos", K = 1, period = 7)  7.284e+00  2.290e+00
                                                   t value Pr(>|t|)    
(Intercept)                                         -3.017 0.002586 ** 
date                                                 3.491 0.000493 ***
lag(value, 1)                                        4.726 2.47e-06 ***
lag(value, 7)                                        3.733 0.000195 ***
lag(value, 14)                                       3.177 0.001512 ** 
lag(value, 21)                                       3.391 0.000711 ***
lag(value, 28)                                       2.879 0.004035 ** 
lag(value, 35)                                       2.302 0.021457 *  
lag(value, 42)                                       2.649 0.008153 ** 
lag(value, 49)                                       2.570 0.010254 *  
month(date, label = TRUE).L                         -2.131 0.033217 *  
month(date, label = TRUE).Q                          0.079 0.936672    
month(date, label = TRUE).C                         -3.218 0.001316 ** 
month(date, label = TRUE)^4                         -1.252 0.210736    
month(date, label = TRUE)^5                         -1.379 0.168099    
month(date, label = TRUE)^6                          0.248 0.803901    
month(date, label = TRUE)^7                         -0.932 0.351248    
month(date, label = TRUE)^8                         -0.838 0.402144    
month(date, label = TRUE)^9                          0.572 0.567064    
month(date, label = TRUE)^10                         0.194 0.846333    
month(date, label = TRUE)^11                        -0.846 0.397797    
fourier_vec(date, type = "sin", K = 1, period = 7)  -5.105 3.66e-07 ***
fourier_vec(date, type = "cos", K = 1, period = 7)   3.180 0.001497 ** 
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Residual standard error: 59.26 on 1765 degrees of freedom
  (49 observations deleted due to missingness)
Multiple R-squared:  0.2297,    Adjusted R-squared:  0.2201 
F-statistic: 23.92 on 22 and 1765 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
            seas <- t(
                sapply(
                    1:25, 
                    function(i) c(
                        i,
                        sqrt(
                            mean((
                                NNS.ARMA(x, 
                                         h = 28, 
                                         training.set = train_set_size, 
                                         method = "lin", 
                                         seasonal.factor = i, 
                                         plot=FALSE
                                         ) - tail(x, 28)) ^ 2)))
                    )
                )
            colnames(seas) <- c("Period", "RMSE")
            sf <- seas[which.min(seas[, 2]), 1]
            
            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( 1 ) ...)"
[1] "CURRENT lin OBJECTIVE FUNCTION = 176.569523303937"
[1] "BEST method = 'lin' PATH MEMBER = c( 1 )"
[1] "BEST lin OBJECTIVE FUNCTION = 176.569523303937"
[1] "CURRNET METHOD: nonlin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 1 ) ...)"
[1] "CURRENT nonlin OBJECTIVE FUNCTION = 25.3448088330466"
[1] "BEST method = 'nonlin' PATH MEMBER = c( 1 )"
[1] "BEST nonlin OBJECTIVE FUNCTION = 25.3448088330466"
[1] "CURRNET METHOD: both"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 1 ) ...)"
[1] "CURRENT both OBJECTIVE FUNCTION = 22.1424663968508"
[1] "BEST method = 'both' PATH MEMBER = c( 1 )"
[1] "BEST both OBJECTIVE FUNCTION = 22.1424663968508"

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( 3 ) ...)"
[1] "CURRENT lin OBJECTIVE FUNCTION = 20.9138420000945"
[1] "BEST method = 'lin' PATH MEMBER = c( 3 )"
[1] "BEST lin OBJECTIVE FUNCTION = 20.9138420000945"
[1] "CURRNET METHOD: nonlin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 3 ) ...)"
[1] "CURRENT nonlin OBJECTIVE FUNCTION = 14.5908630375361"
[1] "BEST method = 'nonlin' PATH MEMBER = c( 3 )"
[1] "BEST nonlin OBJECTIVE FUNCTION = 14.5908630375361"
[1] "CURRNET METHOD: both"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 3 ) ...)"
[1] "CURRENT both OBJECTIVE FUNCTION = 48.0877344990938"
[1] "BEST method = 'both' PATH MEMBER = c( 3 )"
[1] "BEST both OBJECTIVE FUNCTION = 48.0877344990938"

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( 11 ) ...)"
[1] "CURRENT lin OBJECTIVE FUNCTION = 8.9122926658068"
[1] "BEST method = 'lin' PATH MEMBER = c( 11 )"
[1] "BEST lin OBJECTIVE FUNCTION = 8.9122926658068"
[1] "CURRNET METHOD: nonlin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 11 ) ...)"
[1] "CURRENT nonlin OBJECTIVE FUNCTION = 8.71905526248609"
[1] "BEST method = 'nonlin' PATH MEMBER = c( 11 )"
[1] "BEST nonlin OBJECTIVE FUNCTION = 8.71905526248609"
[1] "CURRNET METHOD: both"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 11 ) ...)"
[1] "CURRENT both OBJECTIVE FUNCTION = 8.35463837626691"
[1] "BEST method = 'both' PATH MEMBER = c( 11 )"
[1] "BEST both OBJECTIVE FUNCTION = 8.35463837626691"

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( 11 ) ...)"
[1] "CURRENT lin OBJECTIVE FUNCTION = 14.7944473567488"
[1] "BEST method = 'lin' PATH MEMBER = c( 11 )"
[1] "BEST lin OBJECTIVE FUNCTION = 14.7944473567488"
[1] "CURRNET METHOD: nonlin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 11 ) ...)"
[1] "CURRENT nonlin OBJECTIVE FUNCTION = 24.5861935875251"
[1] "BEST method = 'nonlin' PATH MEMBER = c( 11 )"
[1] "BEST nonlin OBJECTIVE FUNCTION = 24.5861935875251"
[1] "CURRNET METHOD: both"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 11 ) ...)"
[1] "CURRENT both OBJECTIVE FUNCTION = 20.5918707350301"
[1] "BEST method = 'both' PATH MEMBER = c( 11 )"
[1] "BEST both OBJECTIVE FUNCTION = 20.5918707350301"

Package: healthyverse
[1] "CURRNET METHOD: lin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 4 ) ...)"
[1] "CURRENT lin OBJECTIVE FUNCTION = 10.9414658384525"
[1] "BEST method = 'lin' PATH MEMBER = c( 4 )"
[1] "BEST lin OBJECTIVE FUNCTION = 10.9414658384525"
[1] "CURRNET METHOD: nonlin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 4 ) ...)"
[1] "CURRENT nonlin OBJECTIVE FUNCTION = 4.16594400914149"
[1] "BEST method = 'nonlin' PATH MEMBER = c( 4 )"
[1] "BEST nonlin OBJECTIVE FUNCTION = 4.16594400914149"
[1] "CURRNET METHOD: both"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 4 ) ...)"
[1] "CURRENT both OBJECTIVE FUNCTION = 5.28954857371325"
[1] "BEST method = 'both' PATH MEMBER = c( 4 )"
[1] "BEST both OBJECTIVE FUNCTION = 5.28954857371325"

Package: RandomWalker
[1] "CURRNET METHOD: lin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 7 ) ...)"
[1] "CURRENT lin OBJECTIVE FUNCTION = 9.71367670987443"
[1] "BEST method = 'lin' PATH MEMBER = c( 7 )"
[1] "BEST lin OBJECTIVE FUNCTION = 9.71367670987443"
[1] "CURRNET METHOD: nonlin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 7 ) ...)"
[1] "CURRENT nonlin OBJECTIVE FUNCTION = 4.55830718323456"
[1] "BEST method = 'nonlin' PATH MEMBER = c( 7 )"
[1] "BEST nonlin OBJECTIVE FUNCTION = 4.55830718323456"
[1] "CURRNET METHOD: both"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 7 ) ...)"
[1] "CURRENT both OBJECTIVE FUNCTION = 5.0221386561647"
[1] "BEST method = 'both' PATH MEMBER = c( 7 )"
[1] "BEST both OBJECTIVE FUNCTION = 5.0221386561647"

Package: tidyAML
[1] "CURRNET METHOD: lin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 2 ) ...)"
[1] "CURRENT lin OBJECTIVE FUNCTION = 55.9824852532643"
[1] "BEST method = 'lin' PATH MEMBER = c( 2 )"
[1] "BEST lin OBJECTIVE FUNCTION = 55.9824852532643"
[1] "CURRNET METHOD: nonlin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 2 ) ...)"
[1] "CURRENT nonlin OBJECTIVE FUNCTION = 51.0786998186261"
[1] "BEST method = 'nonlin' PATH MEMBER = c( 2 )"
[1] "BEST nonlin OBJECTIVE FUNCTION = 51.0786998186261"
[1] "CURRNET METHOD: both"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 2 ) ...)"
[1] "CURRENT both OBJECTIVE FUNCTION = 95.0599023826288"
[1] "BEST method = 'both' PATH MEMBER = c( 2 )"
[1] "BEST both OBJECTIVE FUNCTION = 95.0599023826288"

Package: TidyDensity
[1] "CURRNET METHOD: lin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'lin' , seasonal.factor =  c( 7 ) ...)"
[1] "CURRENT lin OBJECTIVE FUNCTION = 10.0192470313871"
[1] "BEST method = 'lin' PATH MEMBER = c( 7 )"
[1] "BEST lin OBJECTIVE FUNCTION = 10.0192470313871"
[1] "CURRNET METHOD: nonlin"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'nonlin' , seasonal.factor =  c( 7 ) ...)"
[1] "CURRENT nonlin OBJECTIVE FUNCTION = 9.19230475783876"
[1] "BEST method = 'nonlin' PATH MEMBER = c( 7 )"
[1] "BEST nonlin OBJECTIVE FUNCTION = 9.19230475783876"
[1] "CURRNET METHOD: both"
[1] "COPY LATEST PARAMETERS DIRECTLY FOR NNS.ARMA() IF ERROR:"
[1] "NNS.ARMA(... method =  'both' , seasonal.factor =  c( 7 ) ...)"
[1] "CURRENT both OBJECTIVE FUNCTION = 7.28727379984017"
[1] "BEST method = 'both' PATH MEMBER = c( 7 )"
[1] "BEST both OBJECTIVE FUNCTION = 7.28727379984017"

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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 %>%
  group_by(package) %>%
  # get standardization
  mutate(value_trans = standard_vec(value_trans, silent = TRUE)$standard_scaled) %>%
  tk_augment_fourier(
    .date_var = date,
    .periods  = c(7, 14, 30, 90, 180),
    .K        = 2
  ) %>%
  tk_augment_timeseries_signature(
    .date_var = date
  ) %>%
  ungroup() %>%
  select(-c(value, -year.iso))

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 %>%

    # 0. Filter out column where package is NA
    filter(!is.na(package)) %>%
    
    # 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 [1,829 × 50]> <tibble [28 × 50]> <split [1801|28]>
2 healthyR      <tibble [1,820 × 50]> <tibble [28 × 50]> <split [1792|28]>
3 healthyR.ts   <tibble [1,765 × 50]> <tibble [28 × 50]> <split [1737|28]>
4 healthyverse  <tibble [1,736 × 50]> <tibble [28 × 50]> <split [1708|28]>
5 healthyR.ai   <tibble [1,562 × 50]> <tibble [28 × 50]> <split [1534|28]>
6 TidyDensity   <tibble [1,413 × 50]> <tibble [28 × 50]> <split [1385|28]>
7 tidyAML       <tibble [1,020 × 50]> <tibble [28 × 50]> <split [992|28]> 
8 RandomWalker  <tibble [443 × 50]>   <tibble [28 × 50]> <split [415|28]> 

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

Modeltime Workflow

Recipe Object

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

recipe_base

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

Models

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

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

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

wflw_auto_arima <- workflow() %>%
  add_recipe(recipe = recipe_date) %>%
  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_date) %>%
  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 0.7422748 104.40889 0.7202115 151.84502 0.8922461 0.0968377
healthyR.data 2 LM Test 0.6987373 192.97301 0.6779682 117.83168 0.8215401 0.0023428
healthyR.data 3 EARTH Test 0.7777029 107.95896 0.7545866 162.80981 0.9348008 0.0324979
healthyR.data 4 NNAR Test 0.7203570 206.72307 0.6989452 117.45817 0.8613187 0.0003843
healthyR 1 ARIMA Test 0.6206681 287.08154 0.8913261 139.52289 0.7499832 0.0046133
healthyR 2 LM Test 0.5400077 386.18720 0.7754916 107.96261 0.6462881 0.0788073
healthyR 3 EARTH Test 0.7319908 789.92605 1.0511939 93.29021 0.9226627 0.0142535
healthyR 4 NNAR Test 0.6259143 340.46524 0.8988600 136.10928 0.7197956 0.0380494
healthyR.ts 1 ARIMA Test 0.5880230 219.13526 0.7099583 134.78962 0.7344289 0.0441402
healthyR.ts 2 LM Test 0.7228873 272.47634 0.8727888 140.92345 0.8642904 0.0054960
healthyR.ts 3 EARTH Test 0.5221763 187.38077 0.6304573 109.96546 0.6736939 0.0533812
healthyR.ts 4 NNAR Test 0.7691787 260.00469 0.9286793 153.10259 0.9273533 0.0016830
healthyverse 1 ARIMA Test 0.7027015 105.61902 0.7636533 133.61702 0.9206856 0.0033245
healthyverse 2 LM Test 0.7694518 154.47515 0.8361936 131.74455 0.9033708 0.0068024
healthyverse 3 EARTH Test 0.7074516 95.42670 0.7688155 137.13031 0.9399709 NA
healthyverse 4 NNAR Test 0.7082230 144.40144 0.7696537 125.94000 0.8697719 0.0433339
healthyR.ai 1 ARIMA Test 0.8444300 107.75673 1.0638781 192.18573 1.0229354 0.0289958
healthyR.ai 2 LM Test 1.1174644 188.67375 1.4078680 165.38302 1.3312110 0.0466877
healthyR.ai 3 EARTH Test 0.7115773 99.68899 0.8965000 121.25409 0.9135717 0.0668488
healthyR.ai 4 NNAR Test 1.0468650 171.88162 1.3189214 147.83037 1.2722429 0.0451345
TidyDensity 1 ARIMA Test 1.0870601 275.21574 0.7429908 160.95607 1.2383084 0.0298920
TidyDensity 2 LM Test 0.8672790 128.23374 0.5927733 157.02084 1.0558537 0.0117261
TidyDensity 3 EARTH Test 1.1276602 296.97873 0.7707403 163.71620 1.2568951 0.0000847
TidyDensity 4 NNAR Test 0.9397759 164.68228 0.6423240 167.98021 1.0985928 0.0067000
tidyAML 1 ARIMA Test 0.6294300 108.74555 0.8270355 178.39134 0.7892309 0.0023750
tidyAML 2 LM Test 0.5984350 219.90947 0.7863098 124.16996 0.7656480 0.0482413
tidyAML 3 EARTH Test 0.5491441 152.72646 0.7215443 104.80243 0.6813093 0.1275852
tidyAML 4 NNAR Test 0.6238863 215.07668 0.8197514 122.48301 0.7592986 0.0179053
RandomWalker 1 ARIMA Test 0.6740869 160.64262 0.6767488 146.44368 0.7846548 0.2107023
RandomWalker 2 LM Test 0.8042935 168.79856 0.8074695 160.15269 0.9270806 0.0011328
RandomWalker 3 EARTH Test 0.9254765 218.19338 0.9291310 167.13028 0.9821949 0.0039693
RandomWalker 4 NNAR Test 0.9227835 189.75732 0.9264273 173.69103 1.0451480 0.0643235

Plot Models

nested_modeltime_tbl %>%
  extract_nested_test_forecast() %>%
  group_by(package) %>%
  filter_by_time(.date_var = .index, .start_date = max(.index) - 60) %>%
  ungroup() %>%
  plot_modeltime_forecast(
    .interactive = FALSE,
    .conf_interval_show  = FALSE,
    .facet_scales = "free"
  ) +
  theme_minimal() +
  facet_wrap(~ package, nrow = 3) +
  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  0.699 193.  0.678  118. 0.822 0.00234
2 healthyR             2 LM          Test  0.540 386.  0.775  108. 0.646 0.0788 
3 healthyR.ts          3 EARTH       Test  0.522 187.  0.630  110. 0.674 0.0534 
4 healthyverse         4 NNAR        Test  0.708 144.  0.770  126. 0.870 0.0433 
5 healthyR.ai          3 EARTH       Test  0.712  99.7 0.896  121. 0.914 0.0668 
6 TidyDensity          2 LM          Test  0.867 128.  0.593  157. 1.06  0.0117 
7 tidyAML              3 EARTH       Test  0.549 153.  0.722  105. 0.681 0.128  
8 RandomWalker         1 ARIMA       Test  0.674 161.  0.677  146. 0.785 0.211  
best_nested_modeltime_tbl %>%
  extract_nested_test_forecast() %>%
  #filter(!is.na(.model_id)) %>%
  group_by(package) %>%
  filter_by_time(.date_var = .index, .start_date = max(.index) - 60) %>%
  ungroup() %>%
  plot_modeltime_forecast(
    .interactive = FALSE,
    .conf_interval_alpha = 0.2,
    .facet_scales = "free"
  ) +
  facet_wrap(~ package, nrow = 3) +
  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 [1801|28]> <mdl_tm_t [1 × 5]>
2 healthyR      <tibble>     <tibble>     <split [1792|28]> <mdl_tm_t [1 × 5]>
3 healthyR.ts   <tibble>     <tibble>     <split [1737|28]> <mdl_tm_t [1 × 5]>
4 healthyverse  <tibble>     <tibble>     <split [1708|28]> <mdl_tm_t [1 × 5]>
5 healthyR.ai   <tibble>     <tibble>     <split [1534|28]> <mdl_tm_t [1 × 5]>
6 TidyDensity   <tibble>     <tibble>     <split [1385|28]> <mdl_tm_t [1 × 5]>
7 tidyAML       <tibble>     <tibble>     <split [992|28]>  <mdl_tm_t [1 × 5]>
8 RandomWalker  <tibble>     <tibble>     <split [415|28]>  <mdl_tm_t [1 × 5]>
nested_modeltime_refit_tbl %>%
  extract_nested_future_forecast() %>%
  group_by(package) %>%
  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)) %>%
  filter_by_time(.date_var = .index, .start_date = max(.index) - 60) %>%
  ungroup() %>%
  plot_modeltime_forecast(
    .interactive = FALSE,
    .conf_interval_alpha = 0.2,
    .facet_scales = "free"
  ) +
  facet_wrap(~ package, nrow = 3) +
  theme_minimal() +
  theme(legend.position = "bottom")