Guide to clan and praat



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A Clinician’s Complete Guide to CLAN and PRAAT

Nan Bernstein Ratner

University of Maryland

Shelley Brundage

George Washington University

Last update: 8/27/13

Introduction



WHY you want to learn how to use these programs.
We have all been taught that a language sample is the “gold standard” for evaluating our cases. But you know how tedious a language sample can be, from transcription, to calculating usable clinical scores. We think the last time most clinicians actually DID a language sample was in graduate school. This manual will teach you to use CHAT and CLAN, which will:

  1. Speed up your accurate transcription of data by about ten fold;

  2. Link your transcript to the actual audio or video file you made in the clinic;

  3. Automatically (!!!) compute clinical measures of interest, such as MLU, TTR, DSS, Brown’s morphemes (for children), and a host of other values (WITHOUT MAKING MATH ERRORS!)

  4. Allow you to link to free acoustics software DIRECTLY from the transcript, to calculate values such as speech rate, acoustical features of targeted words or utterances, etc.

  5. Make your OWN targeted analyses of your client’s data

  6. Grammatically tag and analyze data from more than a dozen languages other than English

  7. FOR FREE, with excellent support from a major government supported team that built this wonderful utility, and a list of community users around the world.

The two programs we describe in this manual are:

CLAN

CLAN is a part of the CHILDES system, which provides tools for studying conversational interactions. There are two main parts: the first is used to transcribe sound files in CHAT format and the second, CLAN, is a data analysis programs, used to analyze transcriptions. (For more information, go to http://childes.psy.cmu.edu/)


PRAAT


Praat is a free download program to perform acoustical analysis (see more further in this guide). It intersects directly with CLAN, via the command under MODE: send to sound analyzer drop down menu.

Computer setup

First, turn on your computer  and be connected to the Internet.


Downloading CLAN

To download CLANwin (or the Mac version, Unix, etc.), go to http://childes.psy.cmu.edu/CLAN/.


This is what it looks like for PC users…

There are user manuals for both CHAT and CLAN. You should also download the “CHAT transcription system” manual and the CLAN Programs manual at http://childes.psy.cmu.edu/. These manuals are long and technical, so don’t bother printing it. I recommend saving the CHAT manual and the CLAN manual to your desktop. Importantly, these manuals are searchable by keyword, which may be useful later.


The manual you are reading right now should contain most of what you’ll need to know, but if you have any questions, the manuals described above from this website are much more comprehensive!



KNOWING YOUR COMPUTER’S FILE ORGANIZATION:

It’s kind of surprising, but many folks have gotten so used to working from flash drives or the desktop that they don’t really know where files are stored on their computer. The default directory that gets built when CLAN is installed is called TalkBank.1 It should be located on your C: drive, perhaps like this:


The Talkbank directory has subfolders: the main ones you should get to know are CLAN, LIB, and MOR. To make your life easier, you should also CREATE a folder called MEDIA inside the Talkbank directory. If you store your audios and videos there, the program will easily find them when you try to transcribe things.2

Audio and Video Files
CHAT (the transcription rule system/program in CLAN) allows you to link a transcript directly to audio or video. This speeds up transcription a LOT, and improves its accuracy. Only a few programs actually use the audio or video for analysis; the primary one is exporting an utterance to PRAAT in the CHAT editor window, to do acoustical analysis of what you’ve recorded. Clinicians may want to use PRAAT to analyze features such as speech rate, articulation of individual words, prosodic contour or range for looking at prosody in clients, etc.
The two most commonly used formats that are supported by CLAN are .wav and .mp3.

Although CLAN supports virtually all audio and video formats, it does not recognize files written to DVD. If you wind up needing to transcribe a DVD file, go to the web and find one of the many free audio editing programs that convert DVD to other formats, such as Audacity (http://audacity.sourceforge.net/). If you know that you will be doing acoustical analysis of your samples using the PRAAT interface, be sure that your media works with PRAAT (it is a bit fussier).


How to Transcribe in CHAT

Note: Everything we will talk about below is provided, step by step in a TUTORIAL that uses practice materials, up on the CHILDES web site: http://childes.psy.cmu.edu/ - go to PROGRAMS, then TUTORIAL, and open each tutorial file in sequence.


However, the tutorial starts by bulleting already transcribed materials; we find it more useful to bullet the audio or video first, and then, only if you are a perfectionist, re-bullet the file later to make it align beautifully. So, skip tutorial 04final-useF5, and go to 05-onebullet.
All CHAT transcripts have certain characteristics: Headers, Main Lines, and Dependent Tiers. Each of these is discussed below.
Headers

Headers must be present at the top of every file before you can start transcribing. So, you actually need to write a tiny bit into a file BEFORE you can start transcribing. To open a new, empty CHAT file, double click the CLAN icon. When the program opens, you will see a command window; this window is used for analysis, not for transcription, so you can close it. Then go to the File menu and click on New. This will give you a blank CHAT file where you can begin transcription. YOU MUST TRANSCRIBE IN CLAN, NOT IN A WORD PROCESSOR!!!


Type in the following headers that are needed to start a file:
@Begin

@Languages: eng (for English, use other codes for other languages; see the full manual)

@Participants: CHI Kiddo Child (first word is Tier name, second word is actual identifier/name of your speaker, and third is “role” or function in the interaction (e.g., child, therapist, father), separate speakers by a comma (see next page for example)

@Media: filename, audio OR video

@End

Save this file, and be sure it saves with .cha as the file extension (last 3 letters after the period. Be sure there are NO spaces, periods, commas, or other punctuation in the part BEFORE .cha. Good examples are ARsession1.cha, Kid5age24mos.cha, etc. It will typically store to whatever you marked as your Work directory in CLAN.

OPTIONS FOR INSERTING THE ‘SCARY’ @ID LINES in the Headers from the file we saw above: We are ordering them from easiest and smartest, to less intuitive, but that is just the way I think, so try them.
EASIEST WAY:


  1. Type only the BEGIN, LANGUAGES, PARTICIPANTS, MEDIA and END lines.

  2. Press Esc key, release, and then type ‘l’ (el); a message will pop up telling you that the ID lines have been inserted, and you will see them. Then save your new file.

  3. OR, type only the information in 1. above, THEN open the CLAN Commands window (drop-down under Window tool bar across the top);

  4. TYPE INSERT into the blank command window, then select File In and find your new file. Use Directories and Drives windows to locate your file, then either double click it, or click add to place it in the right-hand window. Then click DONE. This will return you to the Commands window; you will only see an @ sign, not your actual file name. Then click RUN.

This is sort of what it looks like.



This will also automatically put in the ID lines. It will also give the new file a slightly different name, typically .cex; you can rename it, or leave it, or begin learning SOME NEW RULES THAT WORK FOR ALL THE PROGRAMS IN CLAN:

IF YOU ADD THE STRING +1 TO ANY COMMAND, YOUR OUTPUT FILE HAS THE SAME NAME AS YOUR ORIGINAL FILE. That means that if I type:

Insert +1 filename.cha, I will get a message that the program ran and produced a file with exactly the same name. That means that your original file has been overwritten. This is great for stuff like Insert, but could be dangerous when you are just exploring a program with your file. So, remember the option but also remember it can bite you 

The third (and brain-dead) way to make the ID tiers is to save an old file that is properly formatted and just cut and paste the headers from it, and replace the specific information (names, filenames, etc.) for the current file.
The fourth way:

Open your “baby” file in CHAT. Choose the menu option TIERS. Scroll to ID Headers, and the following window will open:




Skip the first line with the pull-down menu;

Enter the 3 letter code for language (eng would be typical); anything without an asterisk is optional. Then name your first speaker on the line that says Name code. CHI (short for Child) or PAR (Participant) would be typical. When you do this, the speaker ID will fill in. Then go down and enter as much info as you know or want in the other fields. When you are done, push DONE and all the lines will insert perfectly in the old file. Then, for any other speakers you are transcribing, go back and do each and you are finished with the header.


Note: You can pull this window down at any time, and it can act as a short set of case history information, such as age, gender, diagnosis, and other notes. When you do it, some of it will then reflect in file headers when you open your CHAT file.

Basic Rules for Headers

1. Every line must end with a carriage return (oops, I am sorry, showing my age, the Enter key; carriage returns are for typewriters; ask your parents what a typewriter is).

2. The first line in the file must be an @Begin header line.

3. The second line in the file must be an @Languages header line, such as “eng” for English.

4. The third line must be an @Participants header line listing three-letter codes for

each participant, the participant's name, and the participant's role.

5. After the @Participants header come a set of @ID headers providing further details for each speaker. These will be inserted automatically for you when you run INSERT.

6. IMPORTANT: Note that the @Media header tells the program which audio file you will be transcribing. They must match EXACTLY. If the title of the audio file does not exactly match the one that you write in the header, then the program will not be able to find the audio. You don’t need to put the file extension in the name; CLAN knows that .mp3 or .wav is audio, .mov is video, etc. Your only options for media are audio or video.

7. The last line in the file (after all the main lines and dependent tiers) must be an @End header line.

MAIN LINES

Lines beginning with * indicate what was actually said. These are called “main lines.” There are some basic rules for coding main lines.


1. Each main line should code one and only one utterance. When a speaker produces several utterances in a row, code each with a new main line.

2. After the asterisk on the main line comes a three-letter code in upper case letters for the participant who was the speaker of the utterance being coded. After the three-letter code comes a colon and then a tab.

3. What was actually said is transcribed starting in the ninth space on the line (using TAB in CLAN brings you automatically to this position. IMPORTANT: Use a tab, not space bar, after each colon.

4. CHAT recognizes a variety of abbreviations for the persons in the audio/video.

However, to make maximal use of comparison databases being built that will allow you to compare a child or an adult with language disorder to typical performance, WE SUGGEST THAT YOU ONLY USE *CHI FOR CHILD CLIENTS/STUDY PARTICIPANTS, AND *PAR FOR ANY ADULT CLIENT/PATIENT/STUDY PARTICIPANT. You CAN pick other three letter codes, but you will lose a lot of the wonderful science you can refer to afterwards if you do that. So, try to listen to this advice! Other typical abbreviations used in the system are MOT for mother and FAT for father and SLP for speech-language pathologist.
DEPENDENT TIERS

Dependent tiers are optional additions to the transcript. These tiers begin with the % symbol and can contain codes and commentary regarding what was said in the Main Tier directly above it. There are some basic rules for coding dependent tiers.

1. The % symbol is followed by a three-letter code in lowercase letters for the dependent tier type, such as “pho” for phonology; a colon; and then a tab. The text of the dependent tier begins after the tab.

2. There are a number of pre-suggested dependent tiers for various purposes; consult the CHAT manual for ideas. You can also insert your own, if you want. But this will require you to adjust a file to make the transcript pass CHECK, so this is an advanced topic (see the back end of this manual for advanced topics). Some programs insert tiers. For instance, the program MOR that we will describe that runs automatically to analyze the grammar in your transcript will insert a %mor dependent tier for you when you run it.

Rules for Words and Utterances

In addition to these minimum requirements for the form of the file, there are certain rules for writing words on the main tier:

1. Utterances should end with an “utterance terminator”. The basic utterance terminators are the period, the exclamation mark, and the question mark. The other common ones are used to mark incomplete or trailing off utterances (see below).

2. Avoid commas. The programs don’t use them for anything.

3. Try to use upper case letters only for proper nouns and the word “I.” If you find that hard, no worry, but many programs will treat “We” and “we” as different words (unless you pick a CLAN option to ignore case).

4. Unintelligible words with an unclear phonetic shape should be transcribed as xxx.

5. If you wish to note the phonological form of an incomplete or unintelligible phonological

string, you can write yyy on the main tier, and insert phonological information below in a %pho tier. This may be more than most language sample analyses really need, however. (Isn’t that why we give articulation tests?)

6. Incomplete words can be written with the omitted material in parentheses, as in

(be)cause and (a)bout.
Here are two samples that illustrate these principles.
@Begin

@Languages: eng

@Participants: CHI Ross Child, FAT Brian Father

@ID: eng|macwhinney|CHI|2;10.10||||Target_Child|||

@ID: eng|macwhinney|FAT|35;2.||||Target_Child|||

@Media: Ross, audio

*ROS: why isn't Mommy coming?

%com: Mother usually picks Ross up around 4 PM.

*FAT: don't worry.

*FAT: she'll be here soon.


*CHI: good.

@End
Here is an example from an adult aphasia patient who is in an Aphasia Bank directory of cases called “Adler”(it has some other codes in it, but dis-regard them for now):
@Begin

@Languages: eng

@Participants: PAR adler02a Participant, INV Investigator

@ID: eng|Adler|PAR|69;9.|male|Conduction|adler02a|Participant||74.9|

@ID: eng|Adler|INV||||adler02a|Investigator|||

@Media: adler02a, video

@G: Speech

*INV: I am gonna [: going to] be asking you to do some talking .

*INV: how do you think your speech is these days ?

*PAR: not good . [+ gram]

*PAR: &=laughs &=head:shake not good . [+ gram]

*PAR: &uh [/] I'm not good a(t) this .

@End


Saving the .cha file and starting the full transcript


  • You will not be able to start transcribing using linked audio until you have saved the file to your computer with a complete set of header information.

  • Remember: Save the file with the exact same name as the audio file except with .cha as the extension. .cha stands for CHAT file format. (E.g., NBR.cha, and NBR.mov, or SSB.cha and SSB.wav)

  • The transcript needs to be saved in the same folder as the audio file.


FINALLY, WE GET TO THE REALLY COOL AND WONDERFUL PART:

Linking text to audio or video

This is the truly wonderful aspect of CHAT/CLAN (SALT cannot do this, sorry). Linking speeds up transcription (up to 3 or 4 times, easily, and perhaps much more), increases transcription accuracy and allows infinite review or analysis of your session. Now you are ready to do this. Read all the steps below before starting this part of the process.


  1. Open CLAN and open your “baby” file that you just formatted.

  2. Close the commands window (Click the X in the upper right of box)

  3. Under the MODE drop down window, select transcribe audio or video OR press the F5 key to begin linking

  4. In the window that pops up, locate the file to which you wish to link. If you get an error that the program can’t locate the file, make sure you have stored it in a media folder inside CLAN. That is the usual problem.

  5. When you click on the necessary file, the recording will begin to play

  6. Each time you hear a silence or natural break, push the space bar. A “bullet” will appear and the cursor will move to the next line. Try inserting 10 to 20 bullets to start, each time you hear a natural break, by pushing the space bar, then you can push any key to stop the process, OR

  7. When you have come to the end of the recording, type @End.

  8. After you have done this, each time you place the cursor by a “bullet” and press F4, you will hear the segment of the recording linked to that line. Transcribe what you hear using the instructions found in this manual. In the section below, we will show you how to make this part even easier!

When you’re finished linking the file, the transcript will look like this:

This looks very strange but is the beginning of something wonderful.

Next, go to the Window menu and open the Walker Controller from the drop down menu. It looks like this:

Many of the terms in this box may seem like gibberish, but the ones you care about are: walk length, loop number, and playback speed. Walk length controls how much you hear when playing back a bullet (if you don’t hear everything you should when you play a bullet, your segment is longer than the default, so just increase this number until you seem to hear enough). LOOP NUMBER is how many times the segment will play while you type – very critical – pick the one that makes you happy! Playback speed controls how fast the playback occurs. 100% is normal, but if the interaction is going too fast, you can decrease rate (and pretend you are transcribing Darth Vader; if you are falling asleep because the person talks too slowly, you can actually make it go faster by setting playback speed to numbers greater than 100% (and transcribe Munchkins). Keep the Walker Controller window open while you do the next steps below.

Click on the first bulleted line. Then click F6. You should hear your segment repeat as many times as you told it to. You are now ready to transcribe. Here is another cool thing: unlike most programs, you can type while having the Walker open – typing won’t deactivate the Walker window.

Now skip down to how to transcribe. Unless you are a perfectionist, in which case read the next paragraph (to get your perfectionism under some level of control):


Don’t worry if your “bullets” (that’s what the dots are called) don’t line up exactly with utterances. THEY ARE PRIMARILY THERE JUST TO MAKE TRANSCRIBING EASIER AND MORE ACCURATE. NO PROGRAMS ACTUALLY COMPARE THE AUDIO/VIDEO BULLETS TO THE TRANSCRIPT. However, if you are the anal-retentive type, you can easily change how much of an utterance is linked to which bullets. To do this:


  1. Put your cursor next to the bullet you want to change. (If you want to add more to the beginning, place the cursor next to the bullet above the one you want to change)

  2. Press F5. The audio will begin to play where that bullet starts

  3. Press the space bar when you want to end that bullet and begin the next one

  4. A black highlighting line will show you which line is currently recording

  5. When you’ve finished fixing the bullet(s), click the mouse anywhere and you will immediately stop recording bullets

How to transcribe:

There are rules for this, for a reason. The programs expect transcripts to look a certain way, or they won’t run, or they will generate gibberish, which makes the whole exercise meaningless. Once you get the hang of it, it’s no different from any other activity in which you are asked to follow a format, such as a web address or a telephone number.3

Main Lines


Lines beginning with * indicate what was actually said. These are called “main lines” or the Main Tier.

A fast way to type in each speaker’s 3 letter code is to pull down the Tiers tab on the top of your file. On the bottom you will see an option called “update”. If you do this, the next time you pick the tiers tab, the first lines going down from the top will be the participants you’ve already identified in the header. Place your cursor in between the asterisk and the colon, press tiers, and either click on the appropriate one, or use the “hot key” to its right. You will get the speaker info inserted automatically.
Important: Each main line should contain only one C-unit.

WHAT THE HECK IS A C-UNIT? A conversational unit (in writing, we use the term T-unit, which is basically the same). A good rule of thumb follows Meatloaf’s wonderful song, “Two out of three ain’t bad”.4 If you haven’t heard it, take a detour and visit: http://www.youtube.com/watch?v=q8JA9Qs2Mho


Although defining an utterance (C-unit) may seem easy, it’s a very real area of disagreement in transcription, as Stockman (2010)5 notes [see these and other references in footnote below]. Because she notes increasing reliability with multiple cues, we have frequently used a “2 out of 3” criterion to define utterances in transcribing. The 3 features are:

  1. Silence or pause of more than 2 seconds

  2. Terminal intonation contour
  3. Syntax that makes a complete sentence, or word(s) that make a complete, appropriate contribution in conversation, as in, MOT: where are you going? CHI: home. (one word, but an utterance)


Our rule is: If you hear two or three of these, you have an utterance. If you hear only one, keep what follows as the same line, utterance, c-unit.
This makes it seem simple. In reality, this is the most subjective and unreliable part of transcription, which is sort of problematic, since so many analyses you want to run, such as MLU, require you to make good decisions about where utterances start and end. If you are doing research using transcripts, it is really important to compute reliability just for this reason alone, as Stockman found. (CLAN offers the RELY program to do this). For child language transcription, both Owens (2010, p 141-2) and Paul & Norbury (2012, p 303)6 have handy charts to use in defining utterances. Most of their longer list reduces to the three criteria listed above.

When a speaker produces several C-units in a row, code each with a new main line.


After the three-letter code is a colon and then tab (not spaces). As we noted above, when you linked the sound file to the transcript, CLAN automatically put in an asterisk and a colon followed by a tab and then the bullet. Using the Tier command then inserts the speaker code, or, if you are a Luddite (look it up), you can simply type the three letter code of the speaker between the asterisk and the colon and then move your cursor directly in front of the bullet and begin typing. This should ensure that the structure of the transcript is correct and consistent. Type what the speaker says and end every line with some sort of punctuation, usually a period. Be sure to place a space between the end of the last word on a line and the punctuation mark.
Here is what a transcript looks like:

Keep the transcript clean (one C-unit per line), even if the bulleted audio does not align exactly. Not every line must contain a bullet, but there is a limit of one bullet per line. Bullets may only occur at the end of the text after the punctuation.



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