4 ms·

I don't think this parser parses left-to-right, like humans and other parsers like Parsley MacParseface do.

by ma2rten 10y ago

botexpert 10y ago
It does. left-to-right linear time parsing is the idea that's about 15 years old and turned out to be most efficient and most performant.
- ma2rten 10y ago
  I might be wrong, but based on the parser home page it looks to me like they provide a Shift-reduce parser but it is not the default. I even says on the page Parser: englishPCFG.ser.gz.
  - botexpert 10y ago
    True, it might not be the case, although they do have the exact same beam search shift-reduce parser that mcparseface has (without the neural net).
kuschku 10y ago
I’m currently writing a paper on improving natural language interfaces for databases, and I’ve ran both Parsey McParseface and Stanford’s CoreNLP for that, and both have horrible performance. Their results for even the most simple english sentences are horrible, often with multiple mistagged words. As soon as you add relative clauses, they break down entirely.
- YeGoblynQueenne 10y ago
  Well, it's not really a solved problem, is it? Saying the performance is "horrible" does some injustice to it. It's actually the state of the art in solutions to a very difficult problem. I've used the Stanford parser for university work (at Masters level). It was part of the pipeline for a sentiment extractor. I didn't get the feeling it performed badly, quite the contrary- the parses it generated were quite useful as features in my extractor. It had this rare feeling of a tool that you can actually use to do something interesting and useful. Then again, I do have my expectations set very lowly, for this sort of thing, especially after completing my Masters thesis (on grammar induction). Language learning is hard.
  - kuschku 10y ago
    I mean, it's surprising how well it works, but if you come in, and expect to get a perfect parse tree out of everything, so you can then easily pattern match on top of that, well, you'll be in for a rouch surprise. Any every slightly more complicated sentence was completely misparsed by CoreNLP and ParseyMcParseface. As I mentioned before, as soon as you introduce relative clauses it breaks down. It's hard when your research was supposed to discuss how to better handle the common knowledge problem of NLIDBs, but you have to spend a lot of time just to get a kinda useful parse out in the first place.

I don't think this parser parses left-to-right, like humans and other parsers like Parsley MacParseface do.

by ma2rten 10y ago

I don't think this parser parses left-to-right, like humans and other parsers like Parsley MacParseface do.

It does. left-to-right linear time parsing is the idea that's about 15 years old and turned out to be most efficient and most performant.

ma2rten 10y ago
I might be wrong, but based on the parser home page it looks to me like they provide a Shift-reduce parser but it is not the default. I even says on the page Parser: englishPCFG.ser.gz.
- botexpert 10y ago
  True, it might not be the case, although they do have the exact same beam search shift-reduce parser that mcparseface has (without the neural net).

kuschku 10y ago

I’m currently writing a paper on improving natural language interfaces for databases, and I’ve ran both Parsey McParseface and Stanford’s CoreNLP for that, and both have horrible performance. Their results for even the most simple english sentences are horrible, often with multiple mistagged words. As soon as you add relative clauses, they break down entirely.

YeGoblynQueenne 10y ago
Well, it's not really a solved problem, is it? Saying the performance is "horrible" does some injustice to it. It's actually the state of the art in solutions to a very difficult problem. I've used the Stanford parser for university work (at Masters level). It was part of the pipeline for a sentiment extractor. I didn't get the feeling it performed badly, quite the contrary- the parses it generated were quite useful as features in my extractor. It had this rare feeling of a tool that you can actually use to do something interesting and useful. Then again, I do have my expectations set very lowly, for this sort of thing, especially after completing my Masters thesis (on grammar induction). Language learning is hard.
- kuschku 10y ago
  I mean, it's surprising how well it works, but if you come in, and expect to get a perfect parse tree out of everything, so you can then easily pattern match on top of that, well, you'll be in for a rouch surprise. Any every slightly more complicated sentence was completely misparsed by CoreNLP and ParseyMcParseface. As I mentioned before, as soon as you introduce relative clauses it breaks down. It's hard when your research was supposed to discuss how to better handle the common knowledge problem of NLIDBs, but you have to spend a lot of time just to get a kinda useful parse out in the first place.