Answers.Body: <p>I offer 3 considerations when trying to answer this question in your own project:</p>
  <ol>
  <li>Does &quot;F0&quot; seem reasonably to have a meaning for the sounds you are considering? For example, sounds are often described as &quot;atonal&quot; or &quot;inharmonic&quot; but this doesn't necessarily mean that they actually lack a fundamental frequency that's driving the sound. You can use your knowledge of the animal's physiology, your own listening, and staring at spectrograms to try and answer this.</li>
  <li>Which F0 algorithm is used, and what are its assumptions/requirements? For example: some algorithms look for a stack of harmonics; some algorithms simply look for any strong energy in a single frequency component. These assumptions influence the kinds of F0 prediction you can expect.
  <ul>
  <li><a href="https://sail.usc.edu/%7Elgoldste/General_Phonetics/Tone/Measurement/Pitch_parameters.html" rel="nofollow noreferrer">It appears that Praat uses autocorrelation-based estimation</a>, which indeed will be positively influenced by the presence of harmonic stacks (which makes sense - suits human vocalisations). For many primate calls I would say it's suitable, though for so-called &quot;nonlinear&quot; calls you may find the F0 estimates might give strange answers that don't match with intuition, since &quot;nonlinear&quot; calls can have complex spectral patterns.</li>
  </ul>
  </li>
  <li>Does the F0 algorithm give an estimate of its &quot;confidence&quot; in the prediction, or the &quot;presence/absence&quot; of an F0? Some algorithms do - in which case, use it. Some algorithms do not, and simply try to give you their &quot;best guess&quot; for every single signal or signal frame they receive. In the latter case, you should apply your beliefs (from point 1 above) much more strongly.
  <ul>
  <li>Praat's algorithm uses a threshold to label frames as &quot;voiced/unvoiced&quot;. This is a standard way to analyse human speech, where the idea of &quot;voiced/unvoiced&quot; phonemes is very common. For your primate calls, this distinction may also be appropriate - however, you shouldn't assume that the threshold settings that work well for human speech will also make the right decisions in your case.</li>
  </ul>
  </li>
  </ol>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2023-07-28T09:55:55.820Z
Answers.LastActivityDate: 2023-07-28T09:55:55.820Z
Answers.UserDisplayName: Dan Stowell
Answers.Body: <p>As I'm not familiar with Praat, I looked up the documentation, especially &quot;Measuring F0 Contours using Praat&quot;, where it states &quot;(it turns out that automatically measuring F0 is not an easy problem)&quot;.</p>
  <p>To estimate any frequency (and therefore F0) one needs only a spectrogram window that windows multiple cycles for the signal.</p>
  <p>I would say, any tonal has a F0, but the presence of a frequency estimation does not need to indicate a tonal signal. Therefore, Praat can easily provide an F0 estimate also for signals that are typically not called tonal.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2023-07-26T11:33:39.663Z
Answers.LastActivityDate: 2023-07-26T17:28:57.923Z
Answers.LastEditDate: 2023-07-26T17:28:57.923Z
Answers.UserDisplayName: WMXZ
Body: <p>In our study, we have chimpanzee pant-grunts. Even if they are atonal calls, Praat manages to automatically extract a F0 for several of them (among other acoustic parameters). We are not sure how reliable that is as atonal calls do not have a F0 and therefore we do not know if it makes sense to include this parameter in our analysis.</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2023-07-26T17:01:17.473Z
Comments.Text: May you have a link with such chimpanzee sound? Praat is usually used for human voice, so it may require to adapt the parameters.
Comments.UserDisplayName: Noil
Tags: <vocalization>
Title: Can F0 parameters be interpreted in atonal calls?
ThreadText: # Can F0 parameters be interpreted in atonal calls?
  
  (Asked by: username_0 on 2023-07-26)
  
  In our study, we have chimpanzee pant-grunts. Even if they are atonal calls, Praat manages to automatically extract a F0 for several of them (among other acoustic parameters). We are not sure how reliable that is as atonal calls do not have a F0 and therefore we do not know if it makes sense to include this parameter in our analysis.
  
  **Tags:** vocalization
  
  > **Comments:**
  > **username_1**: May you have a link with such chimpanzee sound? Praat is usually used for human voice, so it may require to adapt the parameters.  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_2 on 2023-07-28. Score: 2
  
  I offer 3 considerations when trying to answer this question in your own project:
  
  1. Does "F0" seem reasonably to have a meaning for the sounds you are considering? For example, sounds are often described as "atonal" or "inharmonic" but this doesn't necessarily mean that they actually lack a fundamental frequency that's driving the sound. You can use your knowledge of the animal's physiology, your own listening, and staring at spectrograms to try and answer this.
  2. Which F0 algorithm is used, and what are its assumptions/requirements? For example: some algorithms look for a stack of harmonics; some algorithms simply look for any strong energy in a single frequency component. These assumptions influence the kinds of F0 prediction you can expect.
     * [It appears that Praat uses autocorrelation-based estimation](https://sail.usc.edu/%7Elgoldste/General_Phonetics/Tone/Measurement/Pitch_parameters.html), which indeed will be positively influenced by the presence of harmonic stacks (which makes sense - suits human vocalisations). For many primate calls I would say it's suitable, though for so-called "nonlinear" calls you may find the F0 estimates might give strange answers that don't match with intuition, since "nonlinear" calls can have complex spectral patterns.
  3. Does the F0 algorithm give an estimate of its "confidence" in the prediction, or the "presence/absence" of an F0? Some algorithms do - in which case, use it. Some algorithms do not, and simply try to give you their "best guess" for every single signal or signal frame they receive. In the latter case, you should apply your beliefs (from point 1 above) much more strongly.
     * Praat's algorithm uses a threshold to label frames as "voiced/unvoiced". This is a standard way to analyse human speech, where the idea of "voiced/unvoiced" phonemes is very common. For your primate calls, this distinction may also be appropriate - however, you shouldn't assume that the threshold settings that work well for human speech will also make the right decisions in your case.
  
  
  ---
  
  ### Answer by username_3 on 2023-07-26. Score: 0
  
  As I'm not familiar with Praat, I looked up the documentation, especially "Measuring F0 Contours using Praat", where it states "(it turns out that automatically measuring F0 is not an easy problem)".
  
  To estimate any frequency (and therefore F0) one needs only a spectrogram window that windows multiple cycles for the signal.
  
  I would say, any tonal has a F0, but the presence of a frequency estimation does not need to indicate a tonal signal. Therefore, Praat can easily provide an F0 estimate also for signals that are typically not called tonal.
  
  
  ---
  
  