Text-Based Ideal Points

Source code for the paper: Text-Based Ideal Points by Keyon Vafa, Suresh Naidu, and David Blei (ACL 2020).

Update (March 4, 2023): Szymon Sacher's NumPyro implementation of the model is now featured in the NumPyro documentation.

Update (October 31, 2022): See the NumPyro implementation of our model (thanks to Szymon Sacher).

Update (November 16, 2021): We have updated the inference procedure so that Gamma variational families can be used for the positive variables. This allows these variational parameters to be updated directly with coordinate ascent variational inference (CAVI), rather than with reparameterization gradients. As a result, the optimization procedure converges more quickly. Moreover, the learned topics are more interpretable, and they do not need to be initialized with Poisson factorization. The code is here, and an explainer can be found here. Here's a Colab notebook with the new code.

Update (June 29, 2020): We have added interactive visualizations of topics learned by our model.

Update (May 25, 2020): We have added a PyTorch implementation of the text-based ideal point model.

Update (May 11, 2020): See our Colab notebook to run the model online. Our Github code is more complete, and it can be used to reproduce all of our experiments. However, the TBIP is fastest on GPU, so if you do not have access to a GPU you can use Colab's GPUs for free.

Installation for GPU

Configure a virtual environment using Python 3.6+ (instructions here). Inside the virtual environment, use pip to install the required packages:

(venv)$ pip install -r requirements.txt

The main dependencies are Tensorflow (1.14.0) and Tensorflow Probability (0.7.0).

Installation for CPU

To run on CPU, a version of Tensorflow that does not use GPU must be installed. In requirements.txt, comment out the line that says tensorflow-gpu==1.14.0 and uncomment the line that says tensorflow==1.14.0. Note: the script will be noticeably slower on CPU.

Data

Preprocessed Senate speech data for the 114th Congress is included in data/senate-speeches-114. The original data is from [1]. Preprocessed 2020 Democratic presidential candidate tweet data is included in data/candidate-tweets-2020.

To include a customized data set, first create a repo data/{dataset_name}/clean/. The following four files must be inside this folder:

• counts.npz: a [num_documents, num_words] sparse CSR matrix containing the word counts for each document.
• author_indices.npy: a [num_documents] vector where each entry is an integer in the set {0, 1, ..., num_authors - 1}, indicating the author of the corresponding document in counts.npz.
• vocabulary.txt: a [num_words]-length file where each line denotes the corresponding word in the vocabulary.
• author_map.txt: a [num_authors]-length file where each line denotes the name of an author in the corpus.

See data/senate-speeches-114/clean for an example of what the four files look like for Senate speeches. The script setup/senate_speeches_to_bag_of_words.py contains example code for creating the four files from unprocessed data.

Learning text-based ideal points

Run tbip.py to produce ideal points. For the Senate speech data, use the command:

(venv)$ python tbip.py  --data=senate-speeches-114  --batch_size=512  --max_steps=100000

You can view Tensorboard while training to see summaries of training (including the learned ideal points and ideological topics). To run Tensorboard, use the command:

(venv)$ tensorboard  --logdir=data/senate-speeches-114/tbip-fits/  --port=6006

The command should output a link where you can view the Tensorboard results in real time. The fitted parameters will be stored in data/senate-speeches-114/tbip-fits/params. To perform the above analyses for the 2020 Democratic candidate tweets, replace senate-speeches-114 with candidate-tweets-2020.

To run custom data, we recommend training Poisson factorization before running the TBIP script for best results. If you have custom data stored in data/{dataset_name}/clean/, you can run

(venv)$ python setup/poisson_factorization.py  --data={dataset_name}

The default number of topics is 50. To use a different number of topics, e.g. 100, use the flag --num_topics=100. After Poisson factorization finishes, use the following command to run the TBIP:

(venv)$ python tbip.py  --data={dataset_name}

You can adjust the batch size, learning rate, number of topics, and number of steps by using the flags --batch_size, --learning_rate, --num_topics, and --max_steps, respectively. To run the TBIP without initializing from Poisson factorization, use the flag --pre_initialize_parameters=False. To view the results in Tensorboard, run

(venv)$ tensorboard  --logdir=data/{dataset_name}/tbip-fits/  --port=6006

Again, the learned parameters will be stored in data/{dataset_name}/tbip-fits/params.

Reproducing Paper Results

NOTE: Since the publication of our paper, we have made small changes to the code that have sped up inference. A byproduct of these changes is that the Tensorflow graph has changed, so its random seed does not produce the same results as before the changes, even though the data, model, and inference are all the same. To reproduce the exact paper results, one must git checkout to a version of our repository from before these changes:

(venv)$ git checkout 31d161e

The commands below will reproduce all of the paper results. The following data is required before running the commands:

• Senate votes: The original raw data can be found at [2]. The paper includes experiments for Senate sessions 111-114. For each Senate session, we need three files: one for votes, one for members, and one for rollcalls. For example, for Senate session 114, we would use the files: S114_votes.csv, S114_members.csv, S114_rollcalls.csv. Make a repo data/senate-votes and store these three files in data/senate-votes/114/raw/. Repeat for Senate sessions 111-113.
• Senate speeches: The original raw data can be found at [1]. Specifically, we use the hein-daily data for the 114th Senate session. The files needed are speeches_114.txt, descr_114.txt, and 114_SpeakerMap.txt. Make sure the relevant files are stored in data/senate-speeches-114/raw/.
• Senator tweets: The data was provided to us by Voxgov [3].
• Senate speech comparisons: We use a separate data set for the Senate speech comparisons because speech debates must be labeled for Wordshoal. The raw data can be found at [4]. The paper includes experiments for Senate sessions 111-113. We need the files speaker_senator_link_file.csv, speeches_Senate_111.tab, speeches_Senate_112.tab, and speeches_Senate_113.tab. These files should all be stored in data/senate-speech-comparisons/raw/.
• Democratic presidential candidate tweets: Download the raw tweets here and store tweets.csv in the folder data/candidate-tweets-2020/raw/.

Preprocess, run vote ideal point model, and perform analysis for Senate votes

(venv)$ python setup/preprocess_senate_votes.py  --senate_session=111
(venv)$ python setup/preprocess_senate_votes.py  --senate_session=112
(venv)$ python setup/preprocess_senate_votes.py  --senate_session=113
(venv)$ python setup/preprocess_senate_votes.py  --senate_session=114
(venv)$ python setup/vote_ideal_points.py  --senate_session=111
(venv)$ python setup/vote_ideal_points.py  --senate_session=112
(venv)$ python setup/vote_ideal_points.py  --senate_session=113
(venv)$ python setup/vote_ideal_points.py  --senate_session=114
(venv)$ python analysis/analyze_vote_ideal_points.py

Preprocess, run the TBIP, and perform analysis for Senate speeches for the 114th Senate

(venv)$ python setup/senate_speeches_to_bag_of_words.py
(venv)$ python setup/poisson_factorization.py  --data=senate-speeches-114
(venv)$ python tbip.py  --data=senate-speeches-114  --counts_transformation=log  --batch_size=512  --max_steps=150000
(venv)$ python analysis/analyze_senate_speeches.py

Preprocess, run the TBIP and Wordfish, and perform analysis for tweets from senators during the 114th Senate

(venv)$ python setup/senate_tweets_to_bag_of_words.py
(venv)$ python setup/poisson_factorization.py  --data=senate-tweets-114
(venv)$ python tbip.py  --data=senate-tweets-114  --batch_size=1024  --max_steps=100000
(venv)$ python model_comparison/wordfish.py  --data=senate-tweets-114  --max_steps=50000
(venv)$ python analysis/analyze_senate_tweets.py

Preprocess and run the TBIP for Senate speech comparisons

(venv)$ python setup/preprocess_senate_speech_comparisons.py  --senate_session=111
(venv)$ python setup/preprocess_senate_speech_comparisons.py  --senate_session=112
(venv)$ python setup/preprocess_senate_speech_comparisons.py  --senate_session=113
(venv)$ python setup/poisson_factorization.py  --data=senate-speech-comparisons  --senate_session=111
(venv)$ python setup/poisson_factorization.py  --data=senate-speech-comparisons  --senate_session=112
(venv)$ python setup/poisson_factorization.py  --data=senate-speech-comparisons  --senate_session=113
(venv)$ python tbip.py  --data=senate-speech-comparisons  --max_steps=200000  --senate_session=111  --batch_size=128
(venv)$ python tbip.py  --data=senate-speech-comparisons  --max_steps=200000  --senate_session=112  --batch_size=128
(venv)$ python tbip.py  --data=senate-speech-comparisons  --max_steps=200000  --senate_session=113  --batch_size=128

Run Wordfish for Senate speech comparisons

(venv)$ python model_comparison/wordfish.py  --data=senate-speech-comparisons  --max_steps=50000  --senate_session=111
(venv)$ python model_comparison/wordfish.py  --data=senate-speech-comparisons  --max_steps=50000  --senate_session=112 
(venv)$ python model_comparison/wordfish.py  --data=senate-speech-comparisons  --max_steps=50000  --senate_session=113

Run Wordshoal for Senate speech comparisons

(venv)$ python model_comparison/wordshoal.py  --data=senate-speech-comparisons  --max_steps=30000  --senate_session=111  --batch_size=1024
(venv)$ python model_comparison/wordshoal.py  --data=senate-speech-comparisons  --max_steps=30000  --senate_session=112  --batch_size=1024
(venv)$ python model_comparison/wordshoal.py  --data=senate-speech-comparisons  --max_steps=30000  --senate_session=113  --batch_size=1024

Analyze results for Senate speech comparisons

(venv)$ python analysis/compare_tbip_wordfish_wordshoal.py

Preprocess, run the TBIP, and perform analysis for Democratic candidate tweets

(venv)$ python setup/candidate_tweets_to_bag_of_words.py
(venv)$ python setup/poisson_factorization.py  --data=candidate-tweets-2020
(venv)$ python tbip.py  --data=candidate-tweets-2020  --batch_size=1024  --max_steps=100000
(venv)$ python analysis/analyze_candidate_tweets.py

Make figures

(venv)$ python analysis/make_figures.py

References

[1] Matthew Gentzkow, Jesse M. Shapiro, and Matt Taddy. Congressional Record for the 43rd-114th Congresses: Parsed Speeches and Phrase Counts. Palo Alto, CA: Stanford Libraries [distributor], 2018-01-16. https://data.stanford.edu/congress_text

[2] Jeffrey B. Lewis, Keith Poole, Howard Rosenthal, Adam Boche, Aaron Rudkin, and Luke Sonnet (2020). Voteview: Congressional Roll-Call Votes Database. https://voteview.com/

[3] VoxGovFEDERAL, U.S. Senators tweets from the 114th Congress. 2020. https://voxgov.com

[4] Benjamin E. Lauderdale and Alexander Herzog. Replication Data for: Measuring Political Positions from Legislative Speech. In Harvard Dataverse, 2016. https://doi.org/10.7910/DVN/RQMIV3