Vowpal Wabbit is a highly scalable, open source, online machine learning software written in C++. It supports, amongst other features, classification, regression, matrix-factorization, multiple loss functions, multiple update strategies, and regularization.
Questions tagged [vowpalwabbit]
301 questions
6
votes
2 answers
How to install Vowpal Wabbit python interface
VW recently added a python interface, however I am having trouble finding instructions for how to install it. If I install VW from homebrew (brew install vowpal-wabbit) and I open python, and call
import pyvw
I get an ImportError.
Simon
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6
votes
1 answer
Contextual Bandit using Vowpal wabbit
In this case, one of the inputs is the probability of choosing an arm/action but how do we find that probability?
Isn't finding that probability itself a big task in hand?
kunal
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6
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Vowpal Wabbit ignore linear terms, only keep interaction terms
Hi have a Vowpal Wabbit file with two namespaces, for example:
1.0 |A snow |B ski:10
0.0 |A snow |B walk:10
1.0 |A clear |B walk:10
0.0 |A clear |B walk:5
1.0 |A clear |B walk:100
1.0 |A clear |B walk:15
Using -q AB, I can get the interaction…
Manor Lev Tov
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6
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1 answer
Does Vowpal Wabbit shuffle data in multiple online passes?
Does Vowpal Wabbit automatically shuffle its data after every epoch/pass? I'm hoping the created cache file will contain the shuffling meta-data that is necessary for online algorithms like VW's default online SGD method. E.g.
vw -d train.txt -c…
richizy
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6
votes
1 answer
Ordinary Least Squares Regression in Vowpal Wabbit
Has anyone managed to run an ordinary least squares regression in Vowpal Wabbit? I'm trying to confirm that it will return the same answer as the exact solution, i.e. when choosing a to minimize ||y - X a||_2 + ||Ra||_2 (where R is the…
andyInCambridge
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5
votes
1 answer
Vowpal Wabbit: question on training contextual bandit on historical data
I know from this page, that there is an option to train a Contextual Bandit VW model based on historical contextual bandit data collected using some exploration policy:
VW contains a contextual bandit module which allows you to optimize a predictor…
WalksB
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5
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1 answer
Vowpal Wabbit Contextual Bandit Data Formatting
I have 2 questions about formatting data for contextual bandit model training.
If I have data such as below...
1:1:0.2 | d1:us d2:female d3:12
Question 1) I read from VW Wiki that each feature is optionally followed by a float. In case where I have…
Jenna Kwon
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5
votes
3 answers
Vowpal Wabbit - How to get prediction probabilities from contextual bandit model on a test sample
Given a trained contextual bandit model, how can I retrieve a prediction vector on test samples?
For example, let's say I have a train set named "train.dat" containing lines formatted as below
1:-1:0.3 | a b c #
Jenna Kwon
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5
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6 answers
Java API for Vowpal Wabbit?
I am trying to use Vowpal Wabbit through Java. I have downloaded and successfully compiled the code from GitHub. The command line tool works fine.
After having a quick look at the repository (especially here), I can only assume that using it through…
Vongo
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Vowpal Wabbit: What hash function is used exactly?
I'd really like to know which hash function is used for feature hashing in Vowpal Wabbit.
I know that the underlying algorithm is Murmurhash 3, but I couldn't make out the details by looking at the VW code on github.
Does anyone know the exactly…
Kris
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5
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1 answer
How to make vowpal wabbit use more observations
I am new to vowpal wabbit so have some questions about it.
I passed a dataset to the vw and fit a model and got in-sample predictions, saved the model with -f. So far so good. I know how to use the model and make prediction on different dataset.…
DarkHorse
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5
votes
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Vowpal Wabbit training and testing data formats
I'm trying Vowpal Wabbit and am in the process of figuring out the file formats required for training and testing. I've been following the tutorial from https://github.com/JohnLangford/vowpal_wabbit/wiki/Tutorial and see that the following is the…
intl
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5
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2 answers
Interpreting Vowpal Wabbit results: Why are some lines appended by "h"?
Below is part of the log from training my VW model.
Why are some of these lines followed by h? You'll notice that's true of the "average loss" line in the summary at the end. I'm not sure what this means, or if I should care.
...
average since…
jarfa
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Interpreting basic output from Vowpal Wabbit
I had a couple questions about the output from a simple run of VW. I have read around the internet and the wiki sites but am still unsure about a couple of basic things.
I ran the following on the boston housing data:
vw -d housing.vm --progress…
B_Miner
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5
votes
3 answers
Read data from memory in Vowpal Wabbit?
Is there a way to send data to train a model in Vowpal Wabbit without writing it to disk?
Here's what I'm trying to do. I have a relatively large dataset in csv (around 2gb) which fits in memory with no problem. I load it in R into a data frame, and…
user3856970
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