Merge "Return the bigram frequency if available." into jb-dev

main
Jean Chalard 2012-05-17 03:15:40 -07:00 committed by Android (Google) Code Review
commit bc77adefbb
3 changed files with 28 additions and 13 deletions

View File

@ -74,9 +74,9 @@
<item></item> <item></item>
<!-- Modest : Suggestion whose normalized score is greater than this value <!-- Modest : Suggestion whose normalized score is greater than this value
will be subject to auto-correction. --> will be subject to auto-correction. -->
<item>0.22</item> <item>0.185</item>
<!-- Aggressive --> <!-- Aggressive -->
<item>0.08</item> <item>0.067</item>
<!-- Very Aggressive : Suggestion whose normalized score is greater than this value <!-- Very Aggressive : Suggestion whose normalized score is greater than this value
will be subject to auto-correction. --> will be subject to auto-correction. -->
<item>0</item> <item>0</item>

View File

@ -520,19 +520,33 @@ inline int BinaryFormat::getWordAtAddress(const uint8_t* const root, const int a
return 0; return 0;
} }
// This should probably return a probability in log space. static inline int backoff(const int unigramFreq) {
return unigramFreq;
// For some reason, applying the backoff weight gives bad results in tests. To apply the
// backoff weight, we divide the probability by 2, which in our storing format means
// decreasing the score by 8.
// TODO: figure out what's wrong with this.
// return unigramFreq > 8 ? unigramFreq - 8 : (0 == unigramFreq ? 0 : 8);
}
// This returns a probability in log space.
inline int BinaryFormat::getProbability(const int position, const std::map<int, int> *bigramMap, inline int BinaryFormat::getProbability(const int position, const std::map<int, int> *bigramMap,
const uint8_t *bigramFilter, const int unigramFreq) { const uint8_t *bigramFilter, const int unigramFreq) {
if (!bigramMap || !bigramFilter) return unigramFreq; if (!bigramMap || !bigramFilter) return backoff(unigramFreq);
if (!isInFilter(bigramFilter, position)) return unigramFreq; if (!isInFilter(bigramFilter, position)) return backoff(unigramFreq);
const std::map<int, int>::const_iterator bigramFreq = bigramMap->find(position); const std::map<int, int>::const_iterator bigramFreqIt = bigramMap->find(position);
if (bigramFreq != bigramMap->end()) { if (bigramFreqIt != bigramMap->end()) {
// TODO: return the frequency in bigramFreq->second const int bigramFreq = bigramFreqIt->second;
return unigramFreq; // We divide the range [unigramFreq..255] in 16.5 steps - in other words, we want the
// unigram frequency to be the median value of the 17th step from the top. A value of
// 0 for the bigram frequency represents the middle of the 16th step from the top,
// while a value of 15 represents the middle of the top step.
// See makedict.BinaryDictInputOutput for details.
const float stepSize = ((float)MAX_FREQ - unigramFreq) / (1.5f + MAX_BIGRAM_FREQ);
return (int)(unigramFreq + bigramFreq * stepSize);
} else { } else {
return unigramFreq; return backoff(unigramFreq);
} }
// TODO: if the unigram frequency is used, compute the actual probability
} }
} // namespace latinime } // namespace latinime

View File

@ -207,6 +207,7 @@ static inline void prof_out(void) {
#define NEUTRAL_SCORE_SQUARED_RADIUS 8.0f #define NEUTRAL_SCORE_SQUARED_RADIUS 8.0f
#define HALF_SCORE_SQUARED_RADIUS 32.0f #define HALF_SCORE_SQUARED_RADIUS 32.0f
#define MAX_FREQ 255 #define MAX_FREQ 255
#define MAX_BIGRAM_FREQ 15
// This must be greater than or equal to MAX_WORD_LENGTH defined in BinaryDictionary.java // This must be greater than or equal to MAX_WORD_LENGTH defined in BinaryDictionary.java
// This is only used for the size of array. Not to be used in c functions. // This is only used for the size of array. Not to be used in c functions.
@ -225,8 +226,8 @@ static inline void prof_out(void) {
#define MULTIPLE_WORDS_DEMOTION_RATE 80 #define MULTIPLE_WORDS_DEMOTION_RATE 80
#define MIN_INPUT_LENGTH_FOR_THREE_OR_MORE_WORDS_CORRECTION 6 #define MIN_INPUT_LENGTH_FOR_THREE_OR_MORE_WORDS_CORRECTION 6
#define TWO_WORDS_CORRECTION_WITH_OTHER_ERROR_THRESHOLD 0.39 #define TWO_WORDS_CORRECTION_WITH_OTHER_ERROR_THRESHOLD 0.35
#define START_TWO_WORDS_CORRECTION_THRESHOLD 0.22 #define START_TWO_WORDS_CORRECTION_THRESHOLD 0.185
#define MAX_DEPTH_MULTIPLIER 3 #define MAX_DEPTH_MULTIPLIER 3