Package: SII
Type: Package
Title: Calculate ANSI/ASA S3.5-1997 (R2024) Speech Intelligibility
        Index
Version: 1.3.0
Date: 2026-10-03
Authors@R: c(person(given = c("Gregory", "R."), family = "Warnes", role = c("aut", "cph")),
             person(given = "Mark", family = "Shaver", role = c("cre", "aut"), email = "mark.shaver@posteo.net"))
Description: 
   Calculates the American National Standards Institute (ANSI) S3.5-1997
   Speech Intelligibility Index (SII) (ANSI, 1997), a standard method for
   computing the intelligibility of speech from acoustical measurements of
   speech, noise, and hearing thresholds. This package includes data frames
   corresponding to Tables 1 - 4 in the ANSI standard as well as functions
   utilizing these tables and user-provided hearing threshold and noise level
   measurements to compute the SII score. The methods implemented here extend
   the standard computations to allow calculation of SII when the measured
   frequencies do not match those required by the standard by applying
   interpolation. The package also includes a native C++ implementation of
   the 'AUDMOD' specific loudness model for impaired hearing (Bramslow, 2004),
   ported from the 'bramslow2004' implementation in the Auditory Modeling
   Toolbox (AMT), to calculate loudness in sones. It provides methods to
   predict aided SII under hearing aid prescriptive rationales, including
   Open-NL (Open Non-Linear), a theoretical optimization framework that uses
   a Nelder-Mead simplex search to maximize the SII (by default with the
   Johnson and Dillon (2011) desensitization correction), subject to
   loudness penalties and simulated Maximum Power Output (MPO) constraints.
   Further functions calculate real-ear insertion gains, estimate maximum
   power output (SSPL90), and prescribe dynamic range compression. Open-NL
   and the prescription functions are research tools for theoretical
   modeling and simulation; they have not been clinically validated and are
   not intended for fitting hearing aids to patients. Development of this
   package was originally funded by the Center for Bioscience Education and
   Technology (CBET) of the Rochester Institute of Technology (RIT).
Depends: R (>= 3.5.0)
Imports: Rcpp
LinkingTo: Rcpp
Suggests: splines, readxl, xtable, testthat
License: GPL-3 | file LICENSE
LazyLoad: yes
NeedsCompilation: yes
Config/roxygen2/version: 8.1.0
Encoding: UTF-8
Packaged: 2026-10-03 15:57:20 UTC; mark
Author: Gregory R. Warnes [aut, cph],
  Mark Shaver [cre, aut]
Maintainer: Mark Shaver <mark.shaver@posteo.net>
Repository: CRAN
Date/Publication: 2026-10-04 23:01:01 UTC
Built: R 4.5.2; x86_64-apple-darwin20; 2026-10-05 01:07:58 UTC; unix
Archs: SII.so.dSYM
