package edu.stanford.nlp.trees.international.pennchinese;
import edu.stanford.nlp.trees.AbstractCollinsHeadFinder;
import edu.stanford.nlp.trees.TreebankLanguagePack;
import edu.stanford.nlp.util.Generics;
/**
* HeadFinder for the Penn Chinese Treebank. Adapted from
* CollinsHeadFinder. This is the version used in Levy and Manning (2003).
*
* @author Roger Levy
*/
public class ChineseHeadFinder extends AbstractCollinsHeadFinder {
/**
* If true, reverses the direction of search in VP and IP coordinations.
* Works terribly .
*/
private static final boolean coordSwitch = false;
static final String[] leftExceptPunct = {"leftexcept", "PU"};
static final String[] rightExceptPunct = {"rightexcept", "PU"};
public ChineseHeadFinder() {
this(new ChineseTreebankLanguagePack());
}
public ChineseHeadFinder(TreebankLanguagePack tlp) {
super(tlp);
nonTerminalInfo = Generics.newHashMap();
// these are first-cut rules
String left = (coordSwitch ? "right" : "left");
String right = (coordSwitch ? "left" : "right");
String rightdis = "rightdis";
defaultRule = new String[]{right};
// ROOT is not always unary for chinese -- PAIR is a special notation
// that the Irish people use for non-unary ones....
nonTerminalInfo.put("ROOT", new String[][]{{left, "IP"}});
nonTerminalInfo.put("PAIR", new String[][]{{left, "IP"}});
// Major syntactic categories
nonTerminalInfo.put("ADJP", new String[][]{{left, "JJ", "ADJP"}}); // there is one ADJP unary rewrite to AD but otherwise all have JJ or ADJP
nonTerminalInfo.put("ADVP", new String[][]{{left, "AD", "CS", "ADVP", "JJ"}}); // CS is a subordinating conjunctor, and there are a couple of ADVP->JJ unary rewrites
nonTerminalInfo.put("CLP", new String[][]{{right, "M", "CLP"}});
//nonTerminalInfo.put("CP", new String[][] {{left, "WHNP","IP","CP","VP"}}); // this is complicated; see bracketing guide p. 34. Actually, all WHNP are empty. IP/CP seems to be the best semantic head; syntax would dictate DEC/ADVP. Using IP/CP/VP/M is INCREDIBLY bad for Dep parser - lose 3% absolute.
nonTerminalInfo.put("CP", new String[][]{{right, "DEC", "WHNP", "WHPP"}, rightExceptPunct}); // the (syntax-oriented) right-first head rule
// nonTerminalInfo.put("CP", new String[][]{{right, "DEC", "ADVP", "CP", "IP", "VP", "M"}}); // the (syntax-oriented) right-first head rule
nonTerminalInfo.put("DNP", new String[][]{{right, "DEG", "DEC"}, rightExceptPunct}); // according to tgrep2, first preparation, all DNPs have a DEG daughter
nonTerminalInfo.put("DP", new String[][]{{left, "DT", "DP"}}); // there's one instance of DP adjunction
nonTerminalInfo.put("DVP", new String[][]{{right, "DEV", "DEC"}}); // DVP always has DEV under it
nonTerminalInfo.put("FRAG", new String[][]{{right, "VV", "NN"}, rightExceptPunct}); //FRAG seems only to be used for bits at the beginnings of articles: "Xinwenshe<DATE>" and "(wan)"
nonTerminalInfo.put("INTJ", new String[][]{{right, "INTJ", "IJ", "SP"}});
nonTerminalInfo.put("IP", new String[][]{{left, "VP", "IP"}, rightExceptPunct}); // CDM July 2010 following email from Pi-Chuan changed preference to VP over IP: IP can be -SBJ, -OBJ, or -ADV, and shouldn't be head
nonTerminalInfo.put("LCP", new String[][]{{right, "LC", "LCP"}}); // there's a bit of LCP adjunction
nonTerminalInfo.put("LST", new String[][]{{right, "CD", "PU"}}); // covers all examples
nonTerminalInfo.put("NP", new String[][]{{right, "NN", "NR", "NT", "NP", "PN", "CP"}}); // Basic heads are NN/NR/NT/NP; PN is pronoun. Some NPs are nominalized relative clauses without overt nominal material; these are NP->CP unary rewrites. Finally, note that this doesn't give any special treatment of coordination.
nonTerminalInfo.put("PP", new String[][]{{left, "P", "PP"}}); // in the manual there's an example of VV heading PP but I couldn't find such an example with tgrep2
// cdm 2006: PRN changed to not choose punctuation. Helped parsing (if not significantly)
// nonTerminalInfo.put("PRN", new String[][]{{left, "PU"}}); //presumably left/right doesn't matter
nonTerminalInfo.put("PRN", new String[][]{{left, "NP", "VP", "IP", "QP", "PP", "ADJP", "CLP", "LCP"}, {rightdis, "NN", "NR", "NT", "FW"}});
// cdm 2006: QP: add OD -- occurs some; occasionally NP, NT, M; parsing performance no-op
nonTerminalInfo.put("QP", new String[][]{{right, "QP", "CLP", "CD", "OD", "NP", "NT", "M"}}); // there's some QP adjunction
// add OD?
nonTerminalInfo.put("UCP", new String[][]{{left, }}); //an alternative would be "PU","CC"
nonTerminalInfo.put("VP", new String[][]{{left, "VP", "VCD", "VPT", "VV", "VCP", "VA", "VC", "VE", "IP", "VSB", "VCP", "VRD", "VNV"}, leftExceptPunct}); //note that ba and long bei introduce IP-OBJ small clauses; short bei introduces VP
// add BA, LB, as needed
// verb compounds
nonTerminalInfo.put("VCD", new String[][]{{left, "VCD", "VV", "VA", "VC", "VE"}}); // could easily be right instead
nonTerminalInfo.put("VCP", new String[][]{{left, "VCD", "VV", "VA", "VC", "VE"}}); // not much info from documentation
nonTerminalInfo.put("VRD", new String[][]{{left, "VCD", "VRD", "VV", "VA", "VC", "VE"}}); // definitely left
nonTerminalInfo.put("VSB", new String[][]{{right, "VCD", "VSB", "VV", "VA", "VC", "VE"}}); // definitely right, though some examples look questionably classified (na2lai2 zhi1fu4)
nonTerminalInfo.put("VNV", new String[][]{{left, "VV", "VA", "VC", "VE"}}); // left/right doesn't matter
nonTerminalInfo.put("VPT", new String[][]{{left, "VV", "VA", "VC", "VE"}}); // activity verb is to the left
// some POS tags apparently sit where phrases are supposed to be
nonTerminalInfo.put("CD", new String[][]{{right, "CD"}});
nonTerminalInfo.put("NN", new String[][]{{right, "NN"}});
nonTerminalInfo.put("NR", new String[][]{{right, "NR"}});
// I'm adding these POS tags to do primitive morphology for character-level
// parsing. It shouldn't affect anything else because heads of preterminals are not
// generally queried - GMA
nonTerminalInfo.put("VV", new String[][]{{left}});
nonTerminalInfo.put("VA", new String[][]{{left}});
nonTerminalInfo.put("VC", new String[][]{{left}});
nonTerminalInfo.put("VE", new String[][]{{left}});
// new for ctb6.
nonTerminalInfo.put("FLR", new String[][]{rightExceptPunct});
// new for CTB9
nonTerminalInfo.put("DFL", new String[][]{rightExceptPunct});
nonTerminalInfo.put("EMO", new String[][]{leftExceptPunct}); // left/right doesn't matter
nonTerminalInfo.put("INC", new String[][]{leftExceptPunct});
nonTerminalInfo.put("INTJ", new String[][]{leftExceptPunct});
nonTerminalInfo.put("OTH", new String[][]{leftExceptPunct});
nonTerminalInfo.put("SKIP", new String[][]{leftExceptPunct});
}
private static final long serialVersionUID = 6143632784691159283L;
}