Comparison of nuggets and arules performance
In nuggets: Fast and Extensible Pattern Discovery in Tabular Data

knitr::opts_chunk$set(
    collapse = TRUE,
    echo = FALSE,
    comment = "#>",
    fig.width = 7,
    fig.height = 4
)
options(tibble.width = Inf)

library(dplyr)
library(tidyr)
library(ggplot2)
library(patchwork)
library(kableExtra)

preprocess <- function(d) {
    d |>
        pivot_longer(cols = c("nuggets", "arules_apriori", "arules_eclat"),
                     names_to = "method",
                     values_to = "time")  |>
        mutate(time = time / 1e6,  # convert nanoseconds to milli-seconds
               method = dplyr::recode(method,
                                "nuggets" = "nuggets",
                                "arules_apriori" = "apriori (arules)",
                                "arules_eclat" = "eclat (arules)"),
               method = factor(method)) 
}


two_fig <- function(d, x, xname, title) {
    nice_colnames <- c(cols = "# of data columns",
                        rows = "# of data rows",
                        min_support = "min supp",
                        min_confidence = "min conf",
                        max_length = "max ante length")
    fixed <- list()
    for (col in c("rows", "cols", "min_support", "min_confidence", "max_length")) {
        if (length(unique(d[[col]])) == 1) {
            fixed[[col]] <- unique(d[[col]])
        }
    }
    subtitle <- paste0("(",
                       paste(nice_colnames[names(fixed)], fixed, sep = " = ", collapse = ", "),
                       ")")

    p1 <- ggplot(d) +
        aes(x = !!x, y = time, color = method) +
        geom_point() +
        geom_line() +
        labs(title = "linear scales",
             x = xname,
             y = "Time [ms]",
             color = "Method")

    p2 <- ggplot(d) +
        aes(x = !!x, y = time, color = method) +
        geom_point() +
        geom_line() +
        scale_x_log10() +
        scale_y_log10() +
        labs(title = "log scales",
             x = xname,
             y = "Time [ms]",
             color = "Method")

    p1 + p2 +
        plot_annotation(title = title, subtitle = subtitle) +
        plot_layout(ncol = 2, guides = "collect") & theme(legend.position = "bottom") 

}


tab <- function(d, title) {
    d |>
        select(rows, cols, method, time) |>
        mutate(time = round(time, 0)) |>
        pivot_wider(names_from = method, values_from = time) |>
        relocate(`eclat (arules)`, .after = `nuggets`) |>
        arrange(rows, cols) |> 
        #kable(caption = title) |> 
        kable() |> 
        kable_styling(full_width = TRUE) |> 
        add_header_above(c(" " = 1, " " = 1, "Time [ms]" = 3))
}

data <- readRDS("comparison-with-arules.rds")

dense_rows <- data$dense_rows |> preprocess()
dense_cols <- data$dense_cols |> preprocess()
sparse_rows <- data$sparse_rows |> preprocess()
sparse_cols <- data$sparse_cols |> preprocess()

Introduction

This vignette compares the performance of the following R packages:

nuggets r data$nuggets_version
arules r data$arules_version

The task of interest is the discovery of association rules in Boolean (TRUE/FALSE) datasets. The goal is to provide a comparison of brute computational power rather than a full comparison of package functionality, so advanced features, filtering options, and other factors that may affect practical performance are not considered here.

For reproducibility, the benchmark script used in this vignette is available in the package repository on GitHub.

Materials and Methods

A series of experiments were conducted to evaluate the performance of the nuggets and arules packages. For arules, two different algorithms were evaluated: the Apriori algorithm (apriori()) and and the Eclat algorithm (eclat()). For nuggets, the dig_associations() function was used to discover association rules. The experiments were designed to measure the execution time of each method under different conditions, including varying the number of rows and columns in the datasets, as well as the sparsity of the data.

The test datasets were randomly generated with binary values (TRUE/FALSE) and varying numbers of rows and columns. The sparsity of the data was controlled by adjusting the probability of TRUE values in the dataset.

Specifically, the following parameters were varied in the experiments:

number of rows: 10^3^, 10^4^, 10^5^, 10^6^
number of columns: 10, 20, 30, 50, 80
the probability of TRUE values: 0.5 (dense datasets) and 0.1 (sparse datasets)

The other parameters were kept constant across all experiments:

the minimum support threshold: 0.001
the minimum confidence threshold: 0.5 (dense datasets) and 0.1 (sparse datasets)
the maximum length of antecedents: 3

Each experiment was repeated 5 times to ensure the reliability of the results, and the average execution time was recorded. All experiments were conducted on r data$cpu (r data$cache cache) with r round(data$ram, 1) GB of RAM available under the GNU/Linux operating system. The CPU frequency governor was set to "performance" mode and the running process was pinned to a single CPU core.

The results are visualized using both linear and logarithmic scales to provide insights into the performance characteristics of each method.

Results

Dense data: varying number of rows

tab(dense_rows, "Execution time on dense data with varying number of rows")

two_fig(dense_rows, 
        sym("rows"),
        "Number of data rows",
        "Execution time on dense data with varying number of rows")

Dense data: varying number of columns

tab(dense_cols, "Execution time on dense data with varying number of columns")

two_fig(dense_cols, 
        sym("cols"),
        "Number of data columns",
        "Execution time on dense data with varying number of columns")

Sparse data: varying number of rows

tab(sparse_rows, "Execution time on sparse data with varying number of rows")

two_fig(sparse_rows, 
        sym("rows"),
        "Number of data rows",
        "Execution time on sparse data with varying number of rows")

Sparse data: varying number of columns

tab(sparse_cols, "Execution time on sparse data with varying number of columns")

two_fig(sparse_cols, 
        sym("cols"),
        "Number of data columns",
        "Execution time on sparse data with varying number of columns")

Discussion

Similarly as arules:eclat(), nuggets is based on the ECLAT algorithm. Therefore, both variants are expected to perform similarly well. A likely explanation for the strong performance of nuggets on dense data is its highly optimized implementation of conjunction computation and support counting. These operations are central to rule discovery, and in nuggets they are accelerated using:

SIMD instructions via the XSIMD library
highly optimized bit population count via the libpopcnt library

This makes the evaluation of candidate conjunctions fast particularly for dense datasets.

Note that all nuggets optimizations are available with the default compiler directives recommended by CRAN, without requiring any non-standard package installation settings.

Summary

The results show that nuggets is particularly effective for dense data, where its optimized implementation provides consistently strong performance. For sparse data with many predicates, however, arules, especially apriori(), becomes more advantageous.

For additional information on the nuggets package, see:

vignette("nuggets") for an overview of the package and its main workflows,
vignette("association-rules") for a specialized pattern family based on the dig_associations() function,
vignette("conditional-correlations") for subgroup-based correlation analysis on numeric variables,
vignette("contrast-patterns") for subgroup-based statistical comparisons of numeric variables,
vignette("custom-patterns") for defining custom pattern types.