Translates a CSS selector into an equivalent XPath
  expression. This allows us to use CSS selectors when working with
  the XML package as it can only evaluate XPath expressions. Also
  provided are convenience functions useful for using CSS selectors on
  XML nodes. This package is a port of the Python package 'cssselect'
  (<https://cssselect.readthedocs.io/>).

Implements the 'SelectSim' methodology for identifying patterns of
    co-occurrence and mutual exclusivity between functional genomic alterations
    in cancer cohorts. The package processes mutation annotation data, constructs
    alteration matrices, estimates expected alteration-pair frequencies, and
    quantifies deviations associated with selective interactions. The methodology
    is described in Iyer et al. (2026) <doi:10.1038/s41588-026-02661-4>.

Fit and selects point pattern models based on minimum contrast, AIC and and goodness of fit.

Estimates both a vanilla two-way fixed effects (TWFE) model
    and an extended TWFE (ETWFE) model, then selects between them using
    Cochran's Q test for heterogeneity. When ETWFE wins, reports the
    heterogeneity fraction (I-squared) and cohort-time estimates with
    empirical Bayes shrinkage and Bonferroni multiplicity correction.
    Methods build on Wooldridge (2025) <doi:10.1007/s00181-025-02807-z>
    and Callaway and Sant'Anna (2021) <doi:10.1016/j.jeconom.2020.12.001>.

Detection of outliers and influential errors using a latent variable model.

A user-friendly wrapper for web automation, using either
    'chromote' or 'selenium'. Provides a simple and consistent API to make
    web scraping and testing scripts easy to write and understand.
    Elements are lazy, and automatically wait for the website to be valid,
    resulting in reliable and reproducible code, with no visible impact on
    the experience of the programmer.

An implementation of 'W3C WebDriver 2.0'
  (<https://w3c.github.io/webdriver/>), allowing interaction
  with a 'Selenium Server' (<https://www.selenium.dev/documentation/grid/>)
  instance from 'R'. Allows a web browser to be automated from 'R'.