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: 2026-10-09 12:19:25 UTC; root
Author: Gregory R. Warnes [aut, cph], Mark Shaver [cre, aut]
Maintainer: Mark Shaver <mark.shaver@posteo.net>
Repository: https://euphonic-euphemism.r-universe.dev
Date/Publication: 2026-10-05 01:03:12 UTC
RemoteUrl: https://github.com/cran/SII
RemoteRef: HEAD
RemoteSha: a27484bf4b9fbd9be1dc89fe6b6f004f71268e9d
