Python/Gensim - What is the meaning of syn0 and syn0norm?











up vote
0
down vote

favorite












I know that in gensims KeyedVectors-model, one can access the embedding matrix by the attribute model.syn0. There is also a syn0norm, which doesn't seem to work for the glove model I recently loaded. I think I also have seen syn1 somewhere previously.



I haven't found a doc-string for this and I'm just wondering what's the logic behind this?



So if syn0 is the embedding matrix, what is syn0norm? What would then syn1 be and generally, what does syn stand for?










share|improve this question




























    up vote
    0
    down vote

    favorite












    I know that in gensims KeyedVectors-model, one can access the embedding matrix by the attribute model.syn0. There is also a syn0norm, which doesn't seem to work for the glove model I recently loaded. I think I also have seen syn1 somewhere previously.



    I haven't found a doc-string for this and I'm just wondering what's the logic behind this?



    So if syn0 is the embedding matrix, what is syn0norm? What would then syn1 be and generally, what does syn stand for?










    share|improve this question


























      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      I know that in gensims KeyedVectors-model, one can access the embedding matrix by the attribute model.syn0. There is also a syn0norm, which doesn't seem to work for the glove model I recently loaded. I think I also have seen syn1 somewhere previously.



      I haven't found a doc-string for this and I'm just wondering what's the logic behind this?



      So if syn0 is the embedding matrix, what is syn0norm? What would then syn1 be and generally, what does syn stand for?










      share|improve this question















      I know that in gensims KeyedVectors-model, one can access the embedding matrix by the attribute model.syn0. There is also a syn0norm, which doesn't seem to work for the glove model I recently loaded. I think I also have seen syn1 somewhere previously.



      I haven't found a doc-string for this and I'm just wondering what's the logic behind this?



      So if syn0 is the embedding matrix, what is syn0norm? What would then syn1 be and generally, what does syn stand for?







      python deep-learning nlp gensim word-embedding






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Nov 14 at 19:21

























      asked Nov 14 at 13:56









      blue-phoenox

      3,66981440




      3,66981440
























          1 Answer
          1






          active

          oldest

          votes

















          up vote
          1
          down vote



          accepted










          These names were inherited from the original Google word2vec.c implementation, upon which the gensim Word2Vec class was based. (I believe syn0 only exists in recent versions for backward-compatbility.)



          The syn0 array essentially holds raw word-vectors. From the perspective of the neural-network used to train word-vectors, these vectors are a 'projection layer' that can convert a one-hot encoding of a word into a dense embedding-vector of the right dimensionality.



          Similarity operations tend to be done on the unit-normalized versions of the word-vectors. That is, vectors that have all been scaled to have a magnitude of 1.0. (This makes the cosine-similarity calculation easier.) The syn0norm array is filled with these unit-normalized vectors, the first time they're needed.



          This syn0norm will be empty until either you do an operation (like most_similar()) that requires it, or you explicitly do an init_sims() call. If you explicitly do an init_sims(replace=True) call, you'll actually clobber the raw vectors, in-place, with the unit-normed vectors. This saves the memory that storing both vectors for every word would otherwise require. (However, some word-vector uses may still be interested in the original raw vectors of varying magnitudes, so only do this when you're sure most_similar() cosine-similarity operations are all you'll need.)



          The syn1 (or syn1neg in the more common case of negative-sampling training) properties, when they exist on a full model (and not for a plain KeyedVectors object of only word-vectors), are the model neural network's internal 'hidden' weights leading to the output nodes. They're needed during model training, but not a part of the typical word-vectors collected after training.



          I believe the syn prefix is just a convention from neural-network variable-naming, likely derived from 'synapse'.






          share|improve this answer





















          • Great explanation, thank you!
            – blue-phoenox
            Nov 16 at 7:21











          Your Answer






          StackExchange.ifUsing("editor", function () {
          StackExchange.using("externalEditor", function () {
          StackExchange.using("snippets", function () {
          StackExchange.snippets.init();
          });
          });
          }, "code-snippets");

          StackExchange.ready(function() {
          var channelOptions = {
          tags: "".split(" "),
          id: "1"
          };
          initTagRenderer("".split(" "), "".split(" "), channelOptions);

          StackExchange.using("externalEditor", function() {
          // Have to fire editor after snippets, if snippets enabled
          if (StackExchange.settings.snippets.snippetsEnabled) {
          StackExchange.using("snippets", function() {
          createEditor();
          });
          }
          else {
          createEditor();
          }
          });

          function createEditor() {
          StackExchange.prepareEditor({
          heartbeatType: 'answer',
          convertImagesToLinks: true,
          noModals: true,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: 10,
          bindNavPrevention: true,
          postfix: "",
          imageUploader: {
          brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
          contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
          allowUrls: true
          },
          onDemand: true,
          discardSelector: ".discard-answer"
          ,immediatelyShowMarkdownHelp:true
          });


          }
          });














          draft saved

          draft discarded


















          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53301916%2fpython-gensim-what-is-the-meaning-of-syn0-and-syn0norm%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown

























          1 Answer
          1






          active

          oldest

          votes








          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes








          up vote
          1
          down vote



          accepted










          These names were inherited from the original Google word2vec.c implementation, upon which the gensim Word2Vec class was based. (I believe syn0 only exists in recent versions for backward-compatbility.)



          The syn0 array essentially holds raw word-vectors. From the perspective of the neural-network used to train word-vectors, these vectors are a 'projection layer' that can convert a one-hot encoding of a word into a dense embedding-vector of the right dimensionality.



          Similarity operations tend to be done on the unit-normalized versions of the word-vectors. That is, vectors that have all been scaled to have a magnitude of 1.0. (This makes the cosine-similarity calculation easier.) The syn0norm array is filled with these unit-normalized vectors, the first time they're needed.



          This syn0norm will be empty until either you do an operation (like most_similar()) that requires it, or you explicitly do an init_sims() call. If you explicitly do an init_sims(replace=True) call, you'll actually clobber the raw vectors, in-place, with the unit-normed vectors. This saves the memory that storing both vectors for every word would otherwise require. (However, some word-vector uses may still be interested in the original raw vectors of varying magnitudes, so only do this when you're sure most_similar() cosine-similarity operations are all you'll need.)



          The syn1 (or syn1neg in the more common case of negative-sampling training) properties, when they exist on a full model (and not for a plain KeyedVectors object of only word-vectors), are the model neural network's internal 'hidden' weights leading to the output nodes. They're needed during model training, but not a part of the typical word-vectors collected after training.



          I believe the syn prefix is just a convention from neural-network variable-naming, likely derived from 'synapse'.






          share|improve this answer





















          • Great explanation, thank you!
            – blue-phoenox
            Nov 16 at 7:21















          up vote
          1
          down vote



          accepted










          These names were inherited from the original Google word2vec.c implementation, upon which the gensim Word2Vec class was based. (I believe syn0 only exists in recent versions for backward-compatbility.)



          The syn0 array essentially holds raw word-vectors. From the perspective of the neural-network used to train word-vectors, these vectors are a 'projection layer' that can convert a one-hot encoding of a word into a dense embedding-vector of the right dimensionality.



          Similarity operations tend to be done on the unit-normalized versions of the word-vectors. That is, vectors that have all been scaled to have a magnitude of 1.0. (This makes the cosine-similarity calculation easier.) The syn0norm array is filled with these unit-normalized vectors, the first time they're needed.



          This syn0norm will be empty until either you do an operation (like most_similar()) that requires it, or you explicitly do an init_sims() call. If you explicitly do an init_sims(replace=True) call, you'll actually clobber the raw vectors, in-place, with the unit-normed vectors. This saves the memory that storing both vectors for every word would otherwise require. (However, some word-vector uses may still be interested in the original raw vectors of varying magnitudes, so only do this when you're sure most_similar() cosine-similarity operations are all you'll need.)



          The syn1 (or syn1neg in the more common case of negative-sampling training) properties, when they exist on a full model (and not for a plain KeyedVectors object of only word-vectors), are the model neural network's internal 'hidden' weights leading to the output nodes. They're needed during model training, but not a part of the typical word-vectors collected after training.



          I believe the syn prefix is just a convention from neural-network variable-naming, likely derived from 'synapse'.






          share|improve this answer





















          • Great explanation, thank you!
            – blue-phoenox
            Nov 16 at 7:21













          up vote
          1
          down vote



          accepted







          up vote
          1
          down vote



          accepted






          These names were inherited from the original Google word2vec.c implementation, upon which the gensim Word2Vec class was based. (I believe syn0 only exists in recent versions for backward-compatbility.)



          The syn0 array essentially holds raw word-vectors. From the perspective of the neural-network used to train word-vectors, these vectors are a 'projection layer' that can convert a one-hot encoding of a word into a dense embedding-vector of the right dimensionality.



          Similarity operations tend to be done on the unit-normalized versions of the word-vectors. That is, vectors that have all been scaled to have a magnitude of 1.0. (This makes the cosine-similarity calculation easier.) The syn0norm array is filled with these unit-normalized vectors, the first time they're needed.



          This syn0norm will be empty until either you do an operation (like most_similar()) that requires it, or you explicitly do an init_sims() call. If you explicitly do an init_sims(replace=True) call, you'll actually clobber the raw vectors, in-place, with the unit-normed vectors. This saves the memory that storing both vectors for every word would otherwise require. (However, some word-vector uses may still be interested in the original raw vectors of varying magnitudes, so only do this when you're sure most_similar() cosine-similarity operations are all you'll need.)



          The syn1 (or syn1neg in the more common case of negative-sampling training) properties, when they exist on a full model (and not for a plain KeyedVectors object of only word-vectors), are the model neural network's internal 'hidden' weights leading to the output nodes. They're needed during model training, but not a part of the typical word-vectors collected after training.



          I believe the syn prefix is just a convention from neural-network variable-naming, likely derived from 'synapse'.






          share|improve this answer












          These names were inherited from the original Google word2vec.c implementation, upon which the gensim Word2Vec class was based. (I believe syn0 only exists in recent versions for backward-compatbility.)



          The syn0 array essentially holds raw word-vectors. From the perspective of the neural-network used to train word-vectors, these vectors are a 'projection layer' that can convert a one-hot encoding of a word into a dense embedding-vector of the right dimensionality.



          Similarity operations tend to be done on the unit-normalized versions of the word-vectors. That is, vectors that have all been scaled to have a magnitude of 1.0. (This makes the cosine-similarity calculation easier.) The syn0norm array is filled with these unit-normalized vectors, the first time they're needed.



          This syn0norm will be empty until either you do an operation (like most_similar()) that requires it, or you explicitly do an init_sims() call. If you explicitly do an init_sims(replace=True) call, you'll actually clobber the raw vectors, in-place, with the unit-normed vectors. This saves the memory that storing both vectors for every word would otherwise require. (However, some word-vector uses may still be interested in the original raw vectors of varying magnitudes, so only do this when you're sure most_similar() cosine-similarity operations are all you'll need.)



          The syn1 (or syn1neg in the more common case of negative-sampling training) properties, when they exist on a full model (and not for a plain KeyedVectors object of only word-vectors), are the model neural network's internal 'hidden' weights leading to the output nodes. They're needed during model training, but not a part of the typical word-vectors collected after training.



          I believe the syn prefix is just a convention from neural-network variable-naming, likely derived from 'synapse'.







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered Nov 16 at 7:12









          gojomo

          18.1k64364




          18.1k64364












          • Great explanation, thank you!
            – blue-phoenox
            Nov 16 at 7:21


















          • Great explanation, thank you!
            – blue-phoenox
            Nov 16 at 7:21
















          Great explanation, thank you!
          – blue-phoenox
          Nov 16 at 7:21




          Great explanation, thank you!
          – blue-phoenox
          Nov 16 at 7:21


















          draft saved

          draft discarded




















































          Thanks for contributing an answer to Stack Overflow!


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          To learn more, see our tips on writing great answers.





          Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


          Please pay close attention to the following guidance:


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          To learn more, see our tips on writing great answers.




          draft saved


          draft discarded














          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53301916%2fpython-gensim-what-is-the-meaning-of-syn0-and-syn0norm%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown





















































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown

































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown







          Popular posts from this blog

          How to change which sound is reproduced for terminal bell?

          Title Spacing in Bjornstrup Chapter, Removing Chapter Number From Contents

          Can I use Tabulator js library in my java Spring + Thymeleaf project?