Non-Projective Example

I'm looking for an example sentence with a non-projective dependency parse. It doesn't have to be in English, though such an example would be nice.

• What are you looking for? – dainichi May 5 '13 at 15:33
• I think you'll have to indicate what you mean by a "sentence with a non-projective dependency parse", because that's not really a standard term, no matter what your professors said. An example would be nice, especially if it contrasted with an example of a sentence that was minimally distinct in that it does have a projective dependency parse, or a non-projective non-dependency parse, or something else that would allow triangulation. – jlawler May 5 '13 at 16:05

The paper, Non-projective Dependency Parsing using Spanning Tree Algorithms has a few examples of non-projective dependency trees.

Note that dependency graphs are (1) not a formalism and (2) not standardized, so each researcher may re-define what happens in dependencies. Some of those dependency graphs are not even trees. Refer Generating Typed Dependency Parses from Phrase Structure Parses.

• how do you draw these trees in LaTeX?? – CpILL Jul 13 '15 at 10:50
• @CpILL I'm not really big on LaTeX but you can look here: en.wikibooks.org/wiki/LaTeX/Linguistics – prash Jul 13 '15 at 16:32
• @prash So the first sentence is non-projective only because of word 'yesterday'? – Amir Dec 5 '16 at 13:25
• @Amir: It's a combination of two factors, 'yesterday' and 'which was a Yorkshire Terrier'. – prash Dec 5 '16 at 16:50

Here's a different way to look at it: you draw the dependency tree above the sentence with each node aligned with the corresponding word in the sentence, draw a line between the words in the tree and their correspondent in the sentence, and check whether there are any lines intersecting.

The structure below is for the French sentence À qui veux-tu que Pierre parle ? (lit. To whom want you that Peter talks?, 'Who do you want Peter to talk to?'). This sentence is non-projective because à qui has sort of "emancipated" from its governor to position itself relatively to veux. The dependency between parle and à crosses three node projections.

• Yes, nice example. – Tim Osborne Feb 18 '15 at 1:12

Here is a short English example from the paper Non-Projective Dependency Parsing in Expected Linear Time:

Or, if you want it in Universal Dependencies,

Here is the LaTeX code to generate the latter:

\begin{dependency}
\begin{deptext}[column sep=1.2em]
A \& hearing \& is \& scheduled \& on \& the \& issue \& today \\
\end{deptext}
\deproot{4}{root}
\depedge{2}{1}{det}
\depedge{4}{2}{nsubj:pass}
\depedge{4}{3}{aux:pass}
\depedge{7}{5}{case}
\depedge{7}{6}{det}
\depedge[edge start x offset=-6pt]{2}{7}{nmod}
\depedge[edge slant=6pt]{4}{8}{nmod:tmod}
\end{dependency}