# SOME DESCRIPTIVE TITLE.
# Copyright (C) 2023-2024, Samuele Carcagno
# This file is distributed under the same license as the audiometry_trainer
# package.
# FIRST AUTHOR <EMAIL@ADDRESS>, 2024.
#
#, fuzzy
msgid ""
msgstr ""
"Project-Id-Version: audiometry_trainer 0.1.5\n"
"Report-Msgid-Bugs-To: \n"
"POT-Creation-Date: 2024-04-10 15:24+0200\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=utf-8\n"
"Content-Transfer-Encoding: 8bit\n"
"Generated-By: Babel 2.10.3\n"

#: ../../virtual_listener.rst:5
msgid "Virtual listener"
msgstr ""

#: ../../virtual_listener.rst:7
msgid ""
"The responses of the virtual listener are determined by a psychometric "
"function (PF) that represents the proportion of \"Yes\" (I heard a sound)"
" responses as a function of stimulus level. A logistic function "
"([KussEtAl2005]_; [KingdomAndPrins2016]_) is used:"
msgstr ""

#: ../../virtual_listener.rst:9
msgid ""
"\\psi(x;\\alpha,\\beta,\\gamma,\\lambda)  = \\gamma + (1-\\gamma - "
"\\lambda) \\left(\\frac{1}{1+e^{\\beta(\\alpha-x)}}\\right)"
msgstr ""

#: ../../virtual_listener.rst:14
msgid ""
"where :math:`\\alpha` is the midpoint, :math:`\\beta` the slope, "
":math:`\\gamma` the lower asymptote, and :math:`\\lambda` the upper "
"asymptote of the PF; :math:`x` is the stimulus level at which the "
"function is evaluated."
msgstr ""

#: ../../virtual_listener.rst:16
#, python-format
msgid ""
"Figure :ref:`fig-logistic_psy` shows some examples of logistic PFs "
"representing the proportion of a \"Yes\" response as a function of "
"stimulus level. All four panels show the same PF in black together with a"
" function in a different color that has A) a different midpoint, B) a "
"different slope and hence a different width, C) a different lower "
"asymptote, or D) a different upper asymptote. The vertical lines in A) "
"denote the midpoints of the functions, while in B) they denote the "
"\"width\" from 5% to 95% of \"Yes\" responses for the two functions. The "
"horizontal dotted lines in all panels denote the probability of correct "
"responses at the midpoint, note that this changes in C) and D) as a "
"function of the asymptote."
msgstr ""

#: ../../virtual_listener.rst:24
msgid "Logistic psychometric functions"
msgstr ""

#: ../../virtual_listener.rst:26
#, python-format
msgid ""
"The midpoint is the stimulus level at which the PF reaches half of its "
"amplitude, so for a virtual listener with :math:`\\gamma = 0` and "
":math:`\\lambda=0`, the midpoint :math:`\\alpha` is the stimulus level at"
" which the listener gives (on the long run) 50% of \"Yes\" responses. The"
" Hughson-Westlake procedure declares the threshold as the lowest point at"
" which the listener gives at least 50% \"Yes\" responses (over at least 3"
" trials). Therefore, the threshold (as defined with the Hughson-Westlake "
"procedure) will be generally found at or above the midpoint "
":math:`\\alpha` [MarshallAndJesteadt1986]_. Obviously it is possible that"
" on occasion the threshold will be found at a lower level because the "
"proportion of \"Yes\" responses found over a small number of trials may "
"differ from the proportion of \"Yes\" responses expected over the long "
"run."
msgstr ""

#: ../../virtual_listener.rst:28
msgid ""
"The slope :math:`\\beta` controls the speed at which the PF goes from its"
" lowest to its highest value as the stimulus level increases. Rather than"
" reasoning in terms of slope, it is often more intuitive to reason in "
"terms of \"width\" of the PF ([Alcalá-QuintanaAndGarcía-Pérez2004]_; "
"[KussEtAl2005]_), which is inversely correlated with the slope. "
"``audiometry_trainer`` asks the user the desired 90% width of the PF in "
"order to generate case files. For example, a width of 5 dB indicates that"
" the function (for a virtual listener with :math:`\\gamma = 0` and "
":math:`\\lambda=0`) goes from 5% to 95% probability of a \"Yes\" response"
" within a change in stimulus level of 5 dB."
msgstr ""

#: ../../virtual_listener.rst:30
msgid ""
"The lower asymptote, :math:`\\gamma`, represents the propensity of the "
"listener to respond \"Yes\", even in the absence of a stimulus. This "
"propensity is not formally measured in the clinical audiometry procedure "
"[Barr-HamiltonEtAl1969]_ [MarshallAndJesteadt1986]_. In a Yes/No task "
"with temporally marked trials, in which a signal is presented or not, it "
"would correspond to the false alarm rate. For example, a listener with a "
":math:`\\gamma` of 0.1 would respond \"Yes\" in 1 out of 10 trials in "
"which no stimulus was presented. Under the perspective of signal "
"detection theory this propensity of the listener to say \"Yes\" reflects "
"an internal criterion which can be more or less conservative. Although "
"the actual measurement of :math:`\\gamma` requires \"blank\" trials "
"without a signal, the criterion determines the decision process also when"
" a signal is present, hence the value of :math:`\\gamma` will affect the "
"PF underlying the clinical audiometry procedure."
msgstr ""

#: ../../virtual_listener.rst:32
msgid ""
"The upper asymptote, :math:`\\lambda` is the lapse rate, it represents "
"the tendency of the listener to fail responding because of attentional "
"lapses, even for a stimulus that is clearly audible."
msgstr ""

#: ../../virtual_listener.rst:34
msgid ""
"When performing clinical masking with ``audiometry_trainer``, the effect "
"of the noise is to shift the midpoint of the PF, *if* the noise level "
"arriving at the cochlea, in dB of effective masking (EM) units, exceeds "
"the midpoint of the PF. The shift is equal to the level by which the "
"noise exceeds the midpoint. For example, if the noise level is 5 dB above"
" the unmasked midpoint, the masked midpoint will be 5 dB higher."
msgstr ""

#: ../../virtual_listener.rst:36
msgid ""
"Because the effect of the noise varies between listeners, another "
"variable ``msk_diff`` causes a further shift to the PF midpoint in the "
"presence of noise. ``msk_diff`` is randomly drawn from a Normal "
"distribution with a mean of 0 and a standard deviation of 3 for each "
"frequency/ear combination when case files are generated. These values "
"reflect the fact that interindividual differences in the effectiveness of"
" the masking noise will be in the range of ~10 dB (this is the reason why"
" a 10 dB safety pad is typically added to calculated noise levels in "
"masking formulas). It should be noted that ``msk_diff`` can be either "
"positive or negative. A positive ``msk_diff`` means that the masking "
"effect is greater than average (the PF midpoint is shifted upward), while"
" a negative ``msk_diff`` means that the masking effect is smaller than "
"average (the PF midpoint is shifted downward)."
msgstr ""

