Questions tagged [signal-detection]
For questions concerning the area of psychophysics that deals with discernment of information-bearing stimuli from background noise or other distractions.
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Combining Data from Multiple Participants for Statistical Analysis in a Facial Expression Memory Task
I am working on a project involving a memory task for facial expressions, consisting of two phases:
Encoding Phase: There are 8 trials in which participants view 8 different virtual characters, each ...
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How do you model signal detection in an alternative non-forced-choice task?
This question is about signal detection theory for psychology research.
Our study used a memory task where participants were given four options: A, B, C, and "I don't know". I have multiple ...
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Why is threshold at 76% correct when d-prime = 1?
In signal detection theory using a 2-alternative forced choice task, when d' = 1, threshold is found at the stimulus intensity which is perceived 76% of the time (https://www.oxfordreference.com/view/...
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Slope of psychometric function too steep?
I am in a project where we are preparing a visual decision making experiment which requires participants to detect vertical grating in a patch of dynamic noise (the noise pattern is updated on every ...
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How to determine an unbiased estimate of threshold in a single-stimulus forced choice experiment?
Objective
I need to estimate the unbiased threshold of detectable speed difference in a car-following task. The details are as follows:
Experiment Design
This experiment was performed in a driving ...
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Is it possible to calculate d prime if no catch trials were done?
I am new to Psychology, particularly the signal detection theory (SDT). Before understanding SDT, I performed an experiment to measure what speed difference between a subject's car and the front ...
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how to correctly determine false alarm rate (in a specific experimental setup)
i have a specific experimental setup (at least i think so :) It's a replication and i don't know how to correctly determine the false alarm rate for the visual fields since in the article i replicate ...
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130
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conservative vs liberal: not related to rate of yes vs no
I am not a psychology major, so forgive me if I'm misusing terms.
So on an exam, we had a question about signal detection, and it defined a conservative person as someone who always tend to reply ...
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Independence of criterion and d-prime (psychophysics)
I am reading here, page 5 that d' (d-prime) does not vary with criterion (in contrast to hit rate for instance which does vary with criterion, and which can be a biased measure of a subject's ...
user21198
6
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Understanding the concept behind d-prime
I know that sensitivity (d') is typically calculated as follows:
d' = z(Hit Rates) - z (False Alarm Rates)
I understand this as the idea is to standardize both distributions, and to then calculate ...
user21198
2
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1
answer
93
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How to control subject's response bias in 2-interval force choice task
I am using a two-interval force choice (2IFC) task to estimate detection threshold and choose an appropriate signal level for my following experiment, by estimating sensitivity ($d'$) for each signal ...
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Solving for HR and FAR, given ACC and C
Lets say I have an equal variance SDT framework with an equal number of target present and target absent trials:
$d'=Z^{-1}(HR)-Z^{-1}(FAR)$
$C=\frac{Z^{-1}(HR)+Z^{-1}(FAR)}{-2}$
$ACC=\frac{HR+(1-...
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911
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Visual field testing: Choose between Yes/No, 2AFC, and 2IFC task?
As a newbie to psychophysics experiment, I have a small project to do visual field testing on healthy, adult, naive subjects. The experiment stimulus is a small sine grating (0.3 degree, 6 cycles/...
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Fitting equal-variance signal detection model to ROC data
I posted this question in the programming forums but think I might get some answers if I post here as well... hope that's ok.
I'm trying to follow the steps in this paper to reproduce the excel table ...
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Doing PCA and ICA analysis on EEG data with 24 channels
I am very new to this type of neuroscience research and I am trying to do some automatic artifact detection. I am having trouble understanding how I should work with my data. I have data recorded from ...
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