/// <summary>
/// Learn Collocation pairs and triples according to patterns in Treebank-3 tagged files
/// </summary>
/// <remarks>
/// the patterns are from:
/// Justeson, John S., and Slava M. Katz. 1995. Technical terminology: some linguistic properties and
/// an algorithm for identification in text. Natural Language Engineering 1:9-27.
/// </remarks>
/// <returns>IEnumerable of sorted frequencies (KeyValuePairs of collocated terms
/// and the number of occurrrences of that string) of each collocation found in the corpus.
/// </returns>
public static IEnumerable<KeyValuePair<string, double>> collocated_terms_in_Treebank3()
{
var collocated_words_pattern = RegexTools.regex_filter_pattern("<J\\S+|N\\S+><J\\S+|N\\S+|IN\\S|TO\\S>*<N\\S+>");
//Console.WriteLine(collocated_words_pattern);
var treebank3 = new Treebank3CorpusReader(Path.Combine(
Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), @"Data\Treebank-3"));
foreach (var content in treebank3.read_tagged_sents()
.Select((x) => Regex.Match(x, collocated_words_pattern).Groups[0].Value)
.Select((x) => TextTools.get_term_from_string(x).DefaultIfEmpty("").Aggregate((a, b) => a + " " + b))
.Freqs().Generate().OrderBy((x) => x.Value))
{
yield return content;
}
}
public static IEnumerable<KeyValuePair<string, LikelihoodRatio.LikelihoodRatioData<string, string>>> collocations_from_likelihood_ratio_Treebank3()
{
var treebank3 = new Treebank3CorpusReader(Path.Combine(
Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), @"Data\Treebank-3"));
var bigram_freqs = treebank3.words()
.Where((x) => x != ", " && !TextTools.is_puctuation(x) && TextTools.not_whitespace.IsMatch(x))
.NGram(2).Select((a) => a.Aggregate((x, y) => x + " " + y))
.Freqs();
var unigram_freqs = treebank3.words()
.Where((x) => x != ", " && TextTools.not_whitespace.IsMatch(x)).Freqs();
var N = bigram_freqs.Count();
foreach (var bigram_llr in bigram_freqs.Generate())
{
var llr = new LikelihoodRatio.LikelihoodRatioData<string, string>(N
, bigram_llr.Key, bigram_llr.Value, bigram_llr.Key.Split().ToArray(), unigram_freqs);
{
yield return new KeyValuePair<string, LikelihoodRatio.LikelihoodRatioData<string, string>>(bigram_llr.Key, llr);
}
}
// TODO: chi-sqare comparison to gen collocations
}
private static void test_log_likelihood_collocation()
{
var treebank3 = new Treebank3CorpusReader(Path.Combine(
Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), @"Data\Treebank-3"));
var bigram_freqs = treebank3.words()
.Where((x) => x != ", " && !TextTools.is_puctuation(x) && TextTools.not_whitespace.IsMatch(x))
.NGram(2).Select((a) => a.Aggregate((x, y) => x + " " + y))
.Freqs();
var unigram_freqs = treebank3.words()
.Where((x) => x != ", " && TextTools.not_whitespace.IsMatch(x)).Freqs();
foreach (var bigram_llr in LikelihoodRatio.log_likelihood_ratio(unigram_freqs, bigram_freqs).OrderBy((t)=>t.Value).Take(2000))
{
Console.WriteLine(String.Format(@"{0}: {1}", bigram_llr.Key, bigram_llr.Value));
}
}
private static void read_treebank3_period_bigrams()
{
var path = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), @"Data\Treebank-3");
var treebank = new Treebank3CorpusReader(path);
var t1 = treebank.words().Where(x=> (x != "") && x.ToCharArray().Last() == '.');
var t2 = treebank.words().NGram(2).Where(a=>a.Last()==".").Select(a=>a.Aggregate((x,y)=>String.Concat(x,y)));
var t_no_periods = treebank.words().Where(x=> (x != "") && x.ToCharArray().Last() != '.')
.Where((x)=>!TextTools.is_puctuation(x)).NGram(2).Where(a=>a.Last()!=".")
.Select(a=>a.Aggregate((x,y)=>String.Concat(x,y)));
foreach (var content in t1.Union(t2))
{
//var x = content;
Console.WriteLine(content);
}
Console.WriteLine(@"ending period: {0}", t1.Concat(t2).Count());
Console.WriteLine(@" no ending period: {0}", t_no_periods.Count());
Console.WriteLine(@" total: {0}", t_no_periods.Concat(t1.Concat(t2)).Count());
}
private static void read_treebank3()
{
var path = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), @"Data\Treebank-3");
var treebank = new Treebank3CorpusReader(path);
foreach (var content in treebank.words())
{
//var x = content;
Console.WriteLine(content);
}
}
private static void most_common_collocated_NPs_in_Treebank3()
{
var collocated_words_pattern = RegexTools.regex_filter_pattern("<J\\S+|N\\S+><J\\S+|N\\S+|IN\\S|TO\\S>*<N\\S+>");
Console.WriteLine(collocated_words_pattern);
var treebank3 = new Treebank3CorpusReader(Path.Combine(
Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments), @"Data\Treebank-3"));
foreach (var content in treebank3.read_tagged_sents()
.Select((x)=>Regex.Match(x, collocated_words_pattern).Groups[0].Value)
.Select((x) => TextTools.get_term_from_string(x).DefaultIfEmpty("").Aggregate((a, b) => a + " " + b))
.Freqs().Generate().OrderBy((x)=>x.Value).Reverse().Take(1000))
{
Console.WriteLine("{0} : {1}", content.Key, content.Value);
}
}
