<p>I'm new to analyzing QUEST data to produce psychometric functions. I am using Psignifit in Matlab for this.</p>
<p>I have this data:</p>
<p><a href="https://i.sstatic.net/9Y5qe.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/9Y5qe.png" alt="enter image description here" /></a></p>
<p>Column #1 has stimulus contrast presented in the first or the second interval and column #2 (response) says whether the user correctly identified the interval in which it was presented. 1 is correct and 0 is wrong. With QUEST, each contrast level presented is different and there is only row for that particular contrast.</p>
<ol>
<li>How do I use this data (1s and 0s) to get % correct and fit the psychometric function to that data in psignifit in Matlab?</li>
<li>Is there a way to build the psychometric function without binning the data?</li>
</ol>
<p>Any help is appreciated!</p>

CC BY-SA 4.0
2020-08-01T01:33:31.187Z
What sort of shape do you expect the function to have?
Bryan Krause
CC BY-SA 4.0
2020-08-02T13:48:13.177Z
I'm pretty sure you will need to bin the data first.  Why not make the data available and see if anyone will assist?
Tony Mobbs
<measurement>
How to obtain percent correct responses from the QUEST data
Dev1234
# How to obtain percent correct responses from the QUEST data

(Asked by: username_0 on 2020-07-31)

I'm new to analyzing QUEST data to produce psychometric functions. I am using Psignifit in Matlab for this.

I have this data:

[![enter image description here](https://i.sstatic.net/9Y5qe.png)](https://i.sstatic.net/9Y5qe.png)

Column #1 has stimulus contrast presented in the first or the second interval and column #2 (response) says whether the user correctly identified the interval in which it was presented. 1 is correct and 0 is wrong. With QUEST, each contrast level presented is different and there is only row for that particular contrast.

1. How do I use this data (1s and 0s) to get % correct and fit the psychometric function to that data in psignifit in Matlab?
2. Is there a way to build the psychometric function without binning the data?

Any help is appreciated!

**Tags:** measurement

> **Comments:**
> **username_1**: What sort of shape do you expect the function to have?  
> **username_2**: I'm pretty sure you will need to bin the data first.  Why not make the data available and see if anyone will assist?  

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## 0 answers

