A set of simple functions that transforms longitudinal
    data to estimate the cosinor linear model as described in Tong (1976).
    Methods are given to summarize the mean, amplitude and acrophase, to
    predict the mean annual outcome value, and to test the coefficients.

Statistical procedures for calculating population–mean cosinor, non–stationary cosinor, estimation of best–fitting period, tests of population rhythm differences and more. See Cornélissen, G. (2014). <doi:10.1186/1742-4682-11-16>.

Implements the Conditional Ordinal Stereotype Model for Incident-Level Comparison (COSMIC), a method for analyzing ordinal outcomes observed across multiple actors within shared events. The model uses a conditional likelihood to remove event-level confounding and estimate actor-specific propensities relative to their peers. Efficient computation is achieved via a dynamic programming algorithm for the Poisson-multinomial normalization term, enabling scalable estimation with Markov chain Monte Carlo. The package provides tools for data preparation, model fitting using Stan, and extraction of posterior summaries for comparative inference. Estimation of police officer propensity to escalate force is the primary motivation for the model. For more details see Ridgeway (2026) "A Conditional Ordinal Stereotype Model to Estimate Police Officers’ Propensity to Escalate Force" <doi:10.1080/01621459.2025.2597050>.

A data package with 2 main package variables: 'signature' and 'etiology'. 
     The 'signature' variable contains the latest mutational signature profiles 
     released on COSMIC <https://cancer.sanger.ac.uk/signatures/> for 3 mutation
     types:
     * Single base substitutions in the context of preceding and following bases,
     * Doublet base substitutions, and
     * Small insertions and deletions.
    'cosmicsig' stands for COSMIC signatures. Please run ?'cosmicsig' for more
    information.

Package encapsulates standard expressions for distances, times, luminosities, and other quantities useful in observational cosmology, including molecular line observations.  Currently coded for a flat universe only.