Lab 2


The goal of this lab is to make a start on the test suite that will be your development target, on the one hand, and to customize a first version of your grammar start on the other. I've selected phenomena to cover in this lab with an eye to starting with those that are essential to creating a working grammar. You'll probably want to work on these two subtasks in parallel, though they are described separately in the instructions below.

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Test Suite

The first task is to create positive and negative example sentences illustrating the following phenomena, to the extent that they are relevant for your language:

Before you start, read the general instructions for testsuites and the formatting instructions.

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Starter grammar

The second task is to create a starter grammar by filling out the required sections of the Grammar Matrix customization questionnaire. The goal here is to get as much coverage as you can over your test suite using only the customization system (no hand-editing of tdl files yet). In particular, you'll need to address these sections:

In the word order section, you can skip the auxiliaries by saying "no" on that question for now. When we get to auxiliaries, you may of course revise this answer.

In the lexicon section, you should define lexical types for transitive and intransitive verbs and nouns. If appropriate, you should define determiners and case-marking adpositions.

If you have case and/or agreement, you'll need to define morpheme slots and morphemes for verbs and nouns as appropriate. In many languages, the agreement morphemes on verbs also mark, say tense. We'll ignore this for now, but return to it soon. If you want to define other affixes without giving them morphosyntactic content, you can.

Make sure you can parse individual sentences

Once you have created your starter grammar (or each time you create one, as you should iterate through grammar creation and testing a few times as you refine your choices), try it out on a couple of sentences interactively to see if it works:

  1. Load the grammar into the LKB.
  2. Using the parse dialog box (or 'C-c p' in emacs to get the parse command inserted at your prompt), enter a sentence to parse.
  3. Examine the results. If it does parse, check out the semantics (pop-up menu on the little trees). If it doesn't look at the parse chart to see why not.
  4. Problems with lexical rules and lexical entries often become apparent here, too: If the LKB can't find an analysis for one of your words, it will say so, and (obviously) fail to parse the sentence.

Note that the questionnaire has a section for test sentences. If you use this, then the parse dialog will be pre-filled with your test sentences.

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[incr tsdb()] profile

The final step for this lab is to use the [incr tsdb()] grammar profiling system to test the performance of your starter grammar over your test suite, and then examine the results. (You may find in doing so that you want to refine certain aspects of your starter grammar. You can do this by uploading the file "choices" which comes with your grammar into the customization system and then tweaking from there.)

Create a test suite skeleton

  1. Create a directory called tsdb inside your grammar directory.
  2. Inside tsdb, create two subdirectories: home (for test suite instances) and skeletons (for skeletons).
  3. Save a copy of Index.lisp in tsdb/skeletons
  4. Save a copy of Relations in tsdb/skeletons.
  5. Make a subdirectory called lab2 inside tsdb/skeletons for your test suite. (If you choose a different name for this subdirectory, you must edit Index.lisp accordingly.)
  6. Download the perl script and run it on your test suite:

     perl testsuite.txt
  7. (If the perl script doesn't like the formatting of your test suite, edit the test suite appropriately and/or complain about the perl script.)
  8. Copy the .item file which is output by to tsdb/skeletons/lab2/item.
  9. Copy tsdb/skeletons/Relations to tsdb/skeletons/lab2/relations (notice the change from R to r).
  10. The final directory structure should look like this:
    grammar/tsdb/skeletons/Index.lisp            (lists the testsuites)
    grammar/tsdb/skeletons/Relations             (master copy of the database schema)
    grammar/tsdb/skeletons/lab2/item             (copy of ../../data/testsuite.item)
    grammar/tsdb/skeletons/lab2/relations        (copy of ../Relations)
    grammar/tsdb/home                            (directory to store test profiles)

Create and run an initial test suite instance

  1. Start the lkb
  2. Load your starter grammar. (The script file is in your-grammar-dir/lkb/script.)
  3. Start [incr tsdb()] (within emacs, that's M-x itsdb)
  4. In the [incr tsdb()] podium, select Options|Database Root and input the path to tsdb/home.
  5. In the [incr tsdb()] podium, select Options|Skeleton Root and input the path to tsdb/skeletons.
  6. Optional: For future use, you can set these variables ahead of time in a file called .tsdbrc in your home directory. It should contain these lines, with path names edited appropriately:
    (tsdb:tsdb  :skeleton  "path-to-tsdb/home")
    (tsdb:tsdb  :skeleton  "path-to-tsdb/skeletons")
  7. In the [incr tsdb()] podium, select File|Create. You should see your test suite in the menu there. Select it, and get a test suite instance. Post to GoPost if this doesn't work.
  8. Make sure your grammr is loaded into the LKB.
  9. Once you have a test suite instance, select it (by clicking on it), then do Process|All Items.
  10. Explore the results, with functions such as Browse|Results and Analyze|Competence.
  11. Be sure to save (i.e., not overwrite or delete) this test suite instance, as you'll be asked to turn it in.

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Write up

Your write up should be a plain text file (not .doc, .rtf or .pdf) which includes the following:

  1. Documentation the choices you made in the customization system, illustrated with examples from your test suite. Here's an example of what this should look like.
  2. Descriptions of any properties of your language illustrated in your test suite but not covered by your starter grammar and/or the customization system.
  3. Documentation the coverage of your grammar over the testsuite. This should include both summary numbers, which you can get by using the Analyze | Coverage and Analyze | Overgeneration options in [incr tsdb()], and discussion of specific examples. If there are examples that thare parsed incorrectly (unanalyzed grammatical examples, analyzed ungrammatical examples, or grammatical examples assigned surprising parses), reflect on why that might be.
  4. Finally, if there are any places where the customization system seems unable to cope with the properties of your language (within the phenomena addressed in this lab), describe them here.

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Submit your assignment

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Course materials borrow heavily from Linguistics 567: Knowledge Engineering for NLP at the University of Washington. Thanks to Emily Bender for letting us use them.