Language Models are Unsupervised Multitask Learners

Alec Radford * 1 Jeffrey Wu * 1 Rewon Child 1 David Luan 1 Dario Amodei ** 1 Ilya Sutskever ** 1

Abstract
Natural language processing tasks, such as question answering, machine translation, reading comprehension, and summarization, are typicallyapproached with supervised learning on taskspecific datasets. We demonstrate that language
models begin to learn these tasks without any explicit supervision when trained on a new datasetof millions of webpages called WebText. Whenconditioned on a document plus questions, the answers generated by the language model reach 55
F1 on the CoQA dataset - matching or exceeding
the performance of 3 out of 4 baseline systems
without using the 127,000+ training examples.
The capacity of the language model is essential
to the success of zero-shot task transfer and increasing it improves performance in a log-linear
fashion across tasks. Our largest model, GPT-2,
is a 1.5B parameter Transformer that achieves
state of the art results on 7 out of 8 tested language modeling datasets in a zero-shot setting
but still underfits WebText. Samples from themodel reflect these improvements and contain coherent paragraphs of text. These findings suggest
a promising path towards building language processing systems which learn to perform tasks fromtheir naturally occurring demonstrations.

1. Introduction
Machine learning systems now excel (in expectation) at
tasks they are trained for by using a combination of large
datasets, high-capacity models, and supervised learning(Krizhevsky et al., 2012) (Sutskever et al., 2014) (Amodei
et al., 2016). Yet these systems are brittle and sensitive toslight changes in the data distribution (Recht et al., 2018)
and task specification (Kirkpatrick et al., 2017). Current systems are better characterized as narrow experts rather than*, **Equal contribution 1 OpenAI, San Francisco, California, United States.
Correspondence to: Alec Radford<alec@openai.com>.

competent generalists. We would like to move towards moregeneral systems which can perform many tasks – eventually
without the need to manually create and label a training
dataset for each one.
The dominant approach to creating ML systems is to collect a dataset of training examples demonstrating correct
behavior for a desired task, train a system to imitate thesebehaviors, and then test its performance on independentand identically distributed (IID) held-out examples. Thishas served well to make progress on narrow experts. But
the often erratic behavior of captioning models (Lake et al.,2017), reading comprehension systems (Jia & Liang, 2017),
and image classifiers (Alcorn et al., 2018) on the diversityand variety of possible inputs highlights some of the shortcomings of this approach.
Our suspicion is that the prevalence of single task training
on single domain datasets is a major contributor to the lackof generalization observed in current systems. Progress
towards robust systems with current architectures is likely
to require training and measuring performance on a wide
range of domains and tasks. Recently, several benchmarks
have been proposed such as GLUE (Wang et al., 2018) anddecaNLP (McCann et al., 2018) to begin studying this.
Multitask learning (Caruana, 1997) is a promising framework for improving general performance. However, multitask training in NLP is still nascent. Recent work reports modest performance improvements (Yogatama et al.,2019) and the two most ambitious efforts to date havetrained on a total of 10 and 17 (dataset, objective)
pairs respectively (McCann et al., 2018) (Bowman et al.,2018). From a meta-learning perspective, each (dataset,objective) pair is a single training example sampledfrom the distribution of datasets and objectives. Current
ML systems need hundreds to thousands of examples to
induce functions which generalize well. This suggests thatmultitask training many need just as many effective training
pairs to realize its promise with current approaches. It will
be very difficult to continue to scale the creation of datasetsand the design of objectives to the degree that may be required to brute force our way there with current techniques.
This motivates exploring additional setups for performing
multitask learning.
The current best performing systems on language tasks

Language Models are Unsupervised Multitask Learners

Figure 1. Zero-shot task performance of WebText LMs as a function of model size on many NLP tasks. Reading Comprehension results
are on CoQA (Reddy et al., 2018), translation on WMT-14 Fr-En (Artetxe et al., 2017), summarization on CNN and Daily Mail (See et al.,2017), and Question Answering on Natural Questions (Kwiatkowski et al., 2019). Section 3 contains detailed descriptions of each result.

utilize a combination of pre-training and supervised finetuning. This approach has a long history with a trend towards more flexible forms of transfer. First, word vectors
were learned and used as inputs to task-specific architectures (Mikolov et al., 2013) (Collobert et al., 2011), thenthe contextual representations of recurrent networks weretransferred (Dai & Le, 2015) (Peters et al., 2018), and recent work suggests that task-specific architectures are nolonger necessary and transferring many self-attention blocks
is sufficient (Radford et al., 2018) (Devlin et al., 2018).
These methods still require supervised training in orderto perform a task. When only minimal or no supervised
data is available, another line of work has demonstrated
the promise of language models to perform specific tasks,
such as commonsense reasoning (Schwartz et al., 2017) andsentiment analysis (Radford et al., 2017).
In this paper, we connect these two lines of work and continue the trend of more general methods of transfer. We
demonstrate language models can perform down-streamtasks in a zero-shot setting – without any parameter or architecture modification. We demonstrate this approach shows
potential by highlighting the ability of language models toperform a wide range of tasks in a zero-shot setting. We
achieve promising, competitive, and state of the art results
depending on the task.

2. Approach
At the core of our approach is language modeling. Language modeling is usually framed as unsupervised distribution estimation from a set of examples (x1 , x2 , ..., xn )each composed of variable length sequences of symbols(s1 , s2 , ..., sn ). Since language has a natural sequential ordering, it is common to factorize the joint probabilities oversymbols as the product of conditional probabilities (Jelinek& Mercer, 1980) (Bengio et al., 2003):

p(x) =nYp(sn |s1 , ..., sn−1 )

(1)

i=1

This approach allows for tractable sampling from and estimation of p(x) as well as any conditionals of the formp(sn−k , ..., sn |s1 , ..., sn−k−1 ). In recent years, there havebeen significant improvements in the expressiveness of models that can compute these conditional probabilities, such as
self-attention architectures like the Transformer (Vaswani
et al., 2017).
Learning to perform a single task can be expressed in aprobabilistic framework as estimating a conditional distribution p(output|input). Since a general system should be
able to perform many different tasks, even for the same
input, it should condition not only on the input but also
on the task to be performed. That is, it should modelp(output|input, task). This has been variously formalized
in multitask and meta-learning settings. Task conditioning
is often implemented at an architectural level, such as thetask specific encoders and decoders in (Kaiser et al., 2017)
or at an algorithmic level such as the inner and outer loop
optimization framework of MAML (Finn et al., 2017). But
as exemplified in McCann et al. (2018), language provides
a flexible way to specify tasks, inputs, and outputs all as asequence of symbols. For example, a translation training
example can be written as the sequence (translate tofrench, english text, french text). Likewise, a reading comprehension training example canbe written as (answer the question, document,
question, answer). McCann et al. (2018) demonstrated it was possible to train a single model, the MQAN,

Language Models are Unsupervised Multitask Learners

to infer and perform many different tasks on examples withthis type of format.

”I’m not the cleverest man in the world, but like they say in
French: Je ne suis pas un imbecile [I’m not a fool].

Language modeling is also able to, in principle, learn thetasks of McCann et al. (2018) without the need for explicit
supervision of which symbols are the outputs to be predicted. Since the supervised objective is the the same as theunsupervised objective but only evaluated on a subset of thesequence, the global minimum of the unsupervised objectiveis also the global minimum of the supervised objective. In
this slightly toy setting, the concerns with density estimation
as a principled training objective discussed in (Sutskever
et al., 2015) are side stepped. The problem instead becomes
whether we are able to, in practice, optimize the unsupervised objective to convergence. Preliminary experiments
confirmed that sufficiently large language models are able toperform multitask learning in this toy-ish setup but learning
is much slower than in explicitly supervised approaches.

In a now-deleted post from Aug. 16, Soheil Eid, Tory candidatein the riding of Joliette, wrote in French: ”Mentez mentez,
il en restera toujours quelque chose,” which translates as,”Lie lie and something will always remain.”

While it is a large step from the well-posed setup describedabove to the messiness of “language in the wild”, Weston(2016) argues, in the context of dialog, for the need todevelop systems capable of learning from natural language
directly and demonstrated a proof of concept – learning a
QA task without a reward signal by using forward predictionof a teacher’s outputs. While dialog is an attractive approach,
we worry it is overly restrictive. The internet contains a vast
amount of information that is passively available without
the need for interactive communication. Our speculation isthat a language model with sufficient capacity will begin
to learn to infer and perform the tasks demonstrated innatural language sequences in order to better predict them,regardless of their method of procurement. If a language
model is able to do this it will be, in effect, performing
unsupervised multitask learning. We test whether this is thecase by analyzing the performance of language models in azero-shot setting on a wide variety of tasks.
2.1. Training Dataset
Most prior work trained language models on a single domain of text, such as news articles (Jozefowicz et al., 2016),
Wikipedia (Merity et al., 2016), or fiction books (Kiros
et al., 2015). Our approach motivates building as large anddiverse a dataset as possible in order to collect natural language demonstrations of tasks in as varied of domains andcontexts as possible.
A promising source of diverse and nearly unlimited text is
web scrapes such as Common Crawl. While these archives
are many orders of magnitude larger than current language
modeling datasets, they have significant data quality issues.
Trinh & Le (2018) used Common Crawl in their work on
commonsense reasoning but noted a large amount of documents “whose content are mostly unintelligible”. We observed similar data issues in our initial experiments with“I hate the word ‘perfume,”’ Burr says. ‘It’s somewhat better
in French: ‘parfum.’If listened carefully at 29:55, a conversation can be heard
between two guys in French: “-Comment on fait pour aller
de l’autre coté? -Quel autre coté?”, which means “- How
do you get to the other side? - What side?”.
If this sounds like a bit of a stretch, consider this question in French: As-tu aller au cinéma?, or Did you go to
the movies?, which literally translates as Have-you to go to
movies/theater?
“Brevet Sans Garantie Du Gouvernement”, translated toEnglish: “Patented without government warranty”.
Table 1. Examples of naturally occurring demonstrations of English to French and French to English translation found throughout
the WebText training set.

Common Crawl. Trinh & Le (2018)’s best results wereachieved using a small subsample of Common Crawl which
included only documents most similar to their target dataset,the Winograd Schema Challenge. While this is a pragmatic
approach to improve performance on a specific task, wewant to avoid making assumptions about the tasks to be
performed ahead of time.
Instead, we created a new web scrape which emphasizes
document quality. To do this we only scraped web pages
which have been curated/filtered by humans. Manuallyfiltering a full web scrape would be exceptionally expensive
so as a starting point, we scraped all outbound links from
Reddit, a social media platform, which received at least 3
karma. This can be thought of as a heuristic indicator forwhether other users found the link interesting, educational,
or just funny.
The resulting dataset, WebText, contains the text subsetof these 45 million links. To extract the text from HTML
responses we use a combination of the Dragnet (Peters &Lecocq, 2013) and Newspaper1 content extractors. All results presented in this paper use a preliminary version of
WebText which does not include links created after Dec
2017 and which after de-duplication and some heuristic
based cleaning contains slightly over 8 million documents
for a total of 40 GB of text. We removed all Wikipedia
documents from WebText since it is a common data sourcefor other datasets and could complicate analysis due to over1

https://github.com/codelucas/newspaper

Language Models are Unsupervised Multitask Learners

lapping training data with test evaluation tasks.
Parameters2.2. Input Representation
A general language model (LM) should be able to computethe probability of (and also generate) any string. Current
large scale LMs include pre-processing steps such as lowercasing, tokenization, and out-of-vocabulary tokens which
restrict the space of model-able strings. While processing
Unicode strings as a sequence of UTF-8 bytes elegantly fulfills this requirement as exemplified in work such as Gillick
et al. (2015), current byte-level LMs are not competitive
with word-level LMs on large scale datasets such as the
One Billion Word Benchmark (Al-Rfou et al., 2018). We
observed a similar performance gap in our own attempts totrain standard byte-level LMs on WebText.
Byte Pair Encoding (BPE) (Sennrich et al., 2015) is apractical middle ground between character and word level
language modeling which effectively interpolates between
word level inputs for frequent symbol sequences and character level inputs for infrequent symbol sequences. Despite
its name, reference BPE implementations often operate on
Unicode code points and not byte sequences. These implementations would require including the full space of Unicode symbols in order to model all Unicode strings. This
would result in a base vocabulary of over 130,000 before
any multi-symbol tokens are added. This is prohibitively
large compared to the 32,000 to 64,000 token vocabularies
often used with BPE. In contrast, a byte-level version of
BPE only requires a base vocabulary of size 256. However,directly applying BPE to the byte sequence results in suboptimal merges due to BPE using a greedy frequency basedheuristic for building the token vocabulary. We observed
BPE including many versions of common words like dog
since they occur in many variations such as dog. dog!
dog? . This results in a sub-optimal allocation of limited
vocabulary slots and model capacity. To avoid this, we prevent BPE from merging across character categories for any
byte sequence. We add an exception for spaces which significantly improves the compression efficiency while adding
only minimal fragmentation of words across multiple vocab
tokens.
This input representation allows us to combine the empirical
benefits of word-level LMs with the generality of byte-levelapproaches. Since our approach can assign a probability to
any Unicode string, this allows us to evaluate our LMs on
any dataset regardless of pre-processing, tokenization, or
vocab size.
2.3. Model
We use a Transformer (Vaswani et al., 2017) based architecture for our LMs. The model largely follows the detailsof the OpenAI GPT model (Radford et al., 2018) with a

117M
345M
762M
1542M

Layersdmodel

12
24
36
48

768
1024
1280
1600

Table 2. Architecture hyperparameters for the 4 model sizes.

few modifications. Layer normalization (Ba et al., 2016)
was moved to the input of each sub-block, similar to a
pre-activation residual network (He et al., 2016) and an
additional layer normalization was added after the final selfattention block. A modified initialization which accounts
for the accumulation on the residual path with model depth
is used. We scale the weights√ of residual layers at initialization by a factor of 1/ N where N is the number ofresidual layers. The vocabulary is expanded to 50,257. We
also increase the context size from 512 to 1024 tokens anda larger batchsize of 512 is used.

3. Experiments
We trained and benchmarked four LMs with approximately
log-uniformly spaced sizes. The architectures are summarized in Table 2. The smallest model is equivalent to theoriginal GPT, and the second smallest equivalent to thelargest model from BERT (Devlin et al., 2018). Our largest
model, which we call GPT-2, has over an order of magnitude more parameters than GPT. The learning rate of eachmodel was manually tuned for the best perplexity on a 5%
held-out sample of WebText. All models still underfit WebText and held-out perplexity has as of yet improved given
more training time.
3.1. Language Modeling
As an initial step towards zero-shot task transfer, we areinterested in understanding how WebText LM’s performat zero-shot domain transfer on the primary task they aretrained for – language modeling. Since our model operates
on a byte level and does not require lossy pre-processing
or tokenization, we can evaluate it on any language model
benchmark. Results on language modeling datasets arecommonly reported in a quantity which is a scaled or exponentiated version of the average negative log probability
per canonical prediction unit - usually a character, a byte, ora word. We evaluate the same quantity by computing the
log-probability of a dataset according to a WebText LM anddividing by the number of canonical units. For many of thesedatasets, WebText LMs would be tested significantly outof-distribution, having to predict aggressively standardized
text, tokenization artifacts such as disconnected punctuationand contractions, shuffled sentences, and even the string

Language Models are Unsupervised Multitask Learners
LAMBADALAMBADA

CBT-CN

CBT-NE

WikiText2

PTB

enwik8

text8

WikiText103

1BW

(PPL)

(ACC)

(ACC)

(ACC)

(PPL)

(PPL)

(BPB)

(BPC)

(PPL)

(PPL)

SOTA

99.8

59.23

85.7

82.3

39.14

46.54

0.99

1.08

18.3

21.8

117M
345M
762M
1542M

35.13
15.60
10.87
8.63

45.99
55.48
60.12
63.24

87.65
92.35
93.45
93.30

83.4
87.1
88.0
89.05

29.41
22.76
19.93
18.34

65.85
47.33
40.31
35.76

1.16
1.01
0.97
0.93

1.17
1.06
1.02
0.98

37.50
26.37
22.05
17.48

75.20
55.72
44.575
42.16

Table 3. Zero-shot results on many datasets. No training or fine-tuning was performed for any of these results. PTB and WikiText-2
results are from (Gong et al., 2018). CBT results are from (Bajgar et al., 2016). LAMBADA accuracy result is from (Hoang et al., 2018)and LAMBADA perplexity result is from (Grave et al., 2016). Other results are from (Dai et al., 2019).

<UNK> which is extremely rare in WebText - occurring
only 26 times in 40 billion bytes. We report our main results in Table 3 using invertible de-tokenizers which remove
as many of these tokenization / pre-processing artifacts as
possible. Since these de-tokenizers are invertible, we canstill calculate the log probability of a dataset and they canbe thought of as a simple form of domain adaptation. We
observe gains of 2.5 to 5 perplexity for GPT-2 with thesede-tokenizers.
WebText LMs transfer well across domains and datasets,
improving the state of the art on 7 out of the 8 datasets in azero-shot setting. Large improvements are noticed on small
datasets such as Penn Treebank and WikiText-2 which have
only 1 to 2 million training tokens. Large improvements
are also noticed on datasets created to measure long-term
dependencies like LAMBADA (Paperno et al., 2016) andthe Children’s Book Test (Hill et al., 2015). Our model isstill significantly worse than prior work on the One Billion
Word Benchmark (Chelba et al., 2013). This is likely due
to a combination of it being both the largest dataset andhaving some of the most destructive pre-processing - 1BW’ssentence level shuffling removes all long-range structure.
3.2. Children’s Book Test

Figure 2. Performance on the Children’s Book Test as a function ofmodel capacity. Human performance are from Bajgar et al. (2016),
instead of the much lower estimates from the original paper.

The Children’s Book Test (CBT) (Hill et al., 2015) was
created to examine the performance of LMs on different categories of words: named entities, nouns, verbs, and prepositions. Rather than reporting perplexity as an evaluation metric, CBT reports accuracy on an automatically constructedcloze test where the task is to predict which of 10 possible
choices for an omitted word is correct. Following the LM
approach introduced in the original paper, we compute theprobability of each choice and the rest of the sentence conditioned on this choice according to the LM, and predict
the one with the highest probability. As seen in Figure 2
performance steadily improves as model size is increased
and closes the majority of the gap to human performanceon this test. Data overlap analysis showed one of the CBTtest set books, The Jungle Book by Rudyard Kipling, is in
WebText, so we report results on the validation set which
has no significant overlap. GPT-2 achieves new state of theart results of 93.3% on common nouns and 89.1% on namedentities. A de-tokenizer was applied to remove PTB styletokenization artifacts from CBT.
3.3. LAMBADA
The LAMBADA dataset (Paperno et al., 2016) tests theability of systems to model long-range dependencies intext. The task is to predict the final word of sentences
which require at least 50 tokens of context for a human tosuccessfully predict. GPT-2 improves the state of the art
from 99.8 (Grave et al., 2016) to 8.6 perplexity and increases
the accuracy of LMs on this test from 19% (Dehghani et al.,2018) to 52.66%. Investigating GPT-2’s errors showed most
predictions are valid continuations of the sentence, but are
not valid final words. This suggests that the LM is notusing the additional useful constraint that the word must be
the final of the sentence. Adding a stop-word filter as an
approximation to this further increases accuracy to 63.24%,
improving the overall state of the art on this task by 4%. The
previous state of the art (Hoang et al., 2018) used a different
restricted prediction setting where the outputs of the model
were constrained to only words that appeared in the context.
For GPT-2, this restriction is harmful rather than helpful

Language Models are Unsupervised Multitask Learners

since 19% of answers are not in context. We use a versionof the dataset without preprocessing.
3.4. Winograd Schema Challenge

Bottom-Up Sum
Lede-3
Seq2Seq + Attn
GPT-2 TL;DR:
Random-3
GPT-2 no hint

R-1

R-2

R-L

R-AVG

41.22
40.38
31.33
29.34
28.78
21.58

18.68
17.66
11.81
8.27
8.63
4.03

38.34
36.62
28.83
26.58
25.52
19.47

32.75
31.55
23.99
21.40
20.98
15.03

Table 4. Summarization performance as measured by ROUGE F1
metrics on the CNN and Daily Mail dataset. Bottom-Up Sum isthe SOTA model from (Gehrmann et al., 2018)2018), is nearing the 89 F1 performance of humans. While
GPT-2’s performance is exciting for a system without any supervised training, some inspection of its answers and errors
suggests GPT-2 often uses simple retrieval based heuristics
such as answer with a name from the document in response
to a who question.
Figure 3. Performance on the Winograd Schema Challenge as afunction of model capacity.

The Winograd Schema challenge (Levesque et al., 2012)
was constructed to measure the capability of a system toperform commonsense reasoning by measuring its ability
to resolve ambiguities in text. Recently Trinh & Le (2018)
demonstrated significant progress on this challenge usingLMs, by predicting the resolution of the ambiguity withhigher probability. We follow their problem formulation andvisualize the performance of our models with both full andpartial scoring techniques in Figure 3. GPT-2 improves stateof the art accuracy by 7%, achieving 70.70%. The dataset
is quite small with only 273 examples so we recommend
reading Trichelair et al. (2018) to help contextualize thisresult.
3.5. Reading Comprehension
The Conversation Question Answering dataset (CoQA)
Reddy et al. (2018) consists of documents from 7 different
domains paired with natural language dialogues between aquestion asker and a question answerer about the document.
CoQA tests reading comprehension capabilities and also
the ability of models to answer questions that depend on
conversation history (such as “Why?”).
Greedy decoding from GPT-2 when conditioned on a document, the history of the associated conversation, and a
final token A: achieves 55 F1 on the development set. This
matches or exceeds the performance of 3 out of 4 baseline systems without using the 127,000+ manually collected
question answer pairs those baselines were trained on. The
supervised SOTA, a BERT based system (Devlin et al.,3.6. Summarization
We test GPT-2’s ability to perform summarization on the
CNN and Daily Mail dataset (Nallapati et al., 2016). To induce summarization behavior we add the text TL;DR: after
the article and generate 100 tokens with Top-k random sampling (Fan et al., 2018) with k = 2 which reduces repetitionand encourages more abstractive summaries than greedy decoding. We use the first 3 generated sentences in these 100
tokens as the summary. While qualitatively the generations
resemble summaries, as shown in Table 14, they often focus
on recent content from the article or confuse specific details
such as how many cars were involved in a crash or whether
a logo was on a hat or shirt. On the commonly reported
ROUGE 1,2,L metrics the generated summaries only begin
to approach the performance of classic neural baselines andjust barely outperforms selecting 3 random sentences fromthe article. GPT-2’s performance drops by 6.4 points on
the aggregate metric when the task hint is removed which
demonstrates the ability to invoke task specific behavior ina language model with natural language.
3.7. Translation
We test whether GPT-2 has begun to learn how to translatefrom one language to another. In order to help it infer that
this is the desired task, we condition the language model
on a context of example pairs of the format english
sentence = french sentence and then after a final prompt of english sentence = we sample fromthe model with greedy decoding and use the first generated
sentence as the translation. On the WMT-14 English-French
test set, GPT-2 gets 5 BLEU, which is slightly worse thana word-by-word substitution with a bilingual lexicon inferred in previous work on unsupervised word translation

Language Models are Unsupervised Multitask Learners

Question

Generated Answer

Who wrote the book the origin of species?
Who is the founder of the ubuntu project?
Who is the quarterback for the green bay packers?
Panda is a national animal of which country?
Who came up with the theory of relativity?
When was the first star wars film released?
What is the most common blood type in sweden?
Who is regarded as the founder of psychoanalysis?
Who took the first steps on the moon in 1969?
Who is the largest supermarket chain in the uk?
What is the meaning of shalom in english?
Who was the author of the art of war?
Largest state in the us by land mass?
Green algae is an example of which type of reproduction?
Vikram samvat calender is official in which country?
Who is mostly responsible for writing the declaration of independence?
What us state forms the western boundary of montana?
Who plays ser davos in game of thrones?
Who appoints the chair of the federal reserve system?
State the process that divides one nucleus into two genetically identical nuclei?
Who won the most mvp awards in the nba?
What river is associated with the city of rome?
Who is the first president to be impeached?
Who is the head of the department of homeland security 2017?
What is the name given to the common currency to the european union?
What was the emperor name in star wars?
Do you have to have a gun permit to shoot at a range?
Who proposed evolution in 1859 as the basis of biological development?
Nuclear power plant that blew up in russia?
Who played john connor in the original terminator?

Charles Darwin
Mark Shuttleworth
Aaron Rodgers
China
Albert Einstein
1977
A
Sigmund Freud
Neil Armstrong
Tesco
peace
Sun Tzu
California
parthenogenesis
India
Thomas Jefferson
MontanaPeter Dinklage
Janet YellenmitosisMichael Jordan
the Tiber
Andrew Johnson
John Kelly
Euro
Palpatine
No
Charles Darwin
Chernobyl
Arnold Schwarzenegger

Correct

Probability

3
3
3
3
3
3
7
3
3
3
3
3
7
7
3
3
7
7
7
3
7
3
3
3
3
3
3
3
3
7

83.4%
82.0%
81.1%
76.8%
76.4%
71.4%
70.6%
69.3%
66.8%
65.3%
64.0%
59.6%
59.2%
56.5%
55.6%
53.3%
52.3%
52.1%
51.5%
50.7%
50.2%
48.6%
48.3%
47.0%
46.8%
46.5%
46.4%
45.7%
45.7%
45.2%

Table 5. The 30 most confident answers generated by GPT-2 on the development set of Natural Questions sorted by their probability
according to GPT-2. None of these questions appear in WebText according to the procedure described in Section 4.

(Conneau et al., 2017b). On the WMT-14 French-English
test set, GPT-2 is able to leverage its very strong English
language model to perform significantly better, achieving
11.5 BLEU. This outperforms several unsupervised machinetranslation baselines from (Artetxe et al., 2017) and (Lample
et al., 2017) but is still much worse than the 33.5 BLEU of
the current best unsupervised machine translation approach(Artetxe et al., 2019). Performance on this task was surprising to us, since we deliberately removed non-English
webpages from WebText as a filtering step. In order to confirm this, we ran a byte-level language detector2 on WebText
which detected only 10MB of data in the French language
which is approximately 500x smaller than the monolingual
French corpus common in prior unsupervised machine translation research.
3.8. Question Answering
A potential way to test what information is contained withina language model is to evaluate how often it generates thecorrect answer to factoid-style questions. Previous showcasing of this behavior in neural systems where all informationis stored in parameters such as A Neural Conversational
Model (Vinyals & Le, 2015) reported qualitative results dueto the lack of high-quality evaluation datasets. The recently
introduced Natural Questions dataset (Kwiatkowski et al.,2

https://github.com/CLD2Owners/cld2

2019) is a promising resource to test this more quantitatively. Similar to translation, the context of the language
model is seeded with example question answer pairs whichhelps the model infer the short answer style of the dataset.
GPT-2 answers 4.1% of questions correctly when evaluated by the exact match metric commonly used on reading
comprehension datasets like SQUAD.3 As a comparison
point, the smallest model does not exceed the 1.0% accuracy of an incredibly simple baseline which returns the mostcommon answer for each question type (who, what, where,
etc...). GPT-2 answers 5.3 times more questions correctly,
suggesting that model capacity has been a major factor in
the poor performance of neural systems on this kind of task
as of yet. The probability GPT-2 assigns to its generated
answers is well calibrated and GPT-2 has an accuracy of
63.1% on the 1% of questions it is most confident in. The
30 most confident answers generated by GPT-2 on development set questions are shown in Table 5. The performanceof GPT-2 is still much, much, worse than the 30 to 50%
range of open domain question answering systems whichhybridize information retrieval with extractive document
question answering (Alberti et al., 2019).
3

Alec, who previously thought of himself as good at random
trivia, answered 17 of 100 randomly sampled examples correctly
when tested in the same setting as GPT-2. He actually only got 14 right but heshould have gotten those other 3

Language Models are Unsupervised Multitask Learners

PTB

WikiText-2

enwik8text8

Wikitext-103

1BW

Dataset train

2.67%

0.66%

7.50%

2.34%

9.09%

13.19%

WebText train

0.88%

1.63%

6.31%

3.94%

2.42%

3.75%

Table 6. Percentage of test set 8 grams overlapping with training sets.

4. Generalization vs Memorization

gave away the answer.

Recent work in computer vision has shown that common image datasets contain a non-trivial amount of near-duplicate
images. For instance CIFAR-10 has 3.3% overlap between
train and test images (Barz & Denzler, 2019). This results inan over-reporting of the generalization performance of machine learning systems. As the size of datasets increases thisissue becomes increasingly likely which suggests a similar
phenomena could be happening with WebText. Therefore it
is important to analyze how much test data also shows up in
the training data.

For CoQA, about 15% of documents in the news domain
are already in WebText and the model performs about 3
F1 better on these. CoQA’s development set metric reports
the average performance over 5 different domains and wemeasure a gain of about 0.5-1.0 F1 due to overlap across thevarious domains. However, no actual training questions or
answers are in WebText since CoQA was released after thecutoff date for links in WebText.

To study this we created Bloom filters containing 8-gramsof WebText training set tokens. To improve recall, strings
were normalized to contain only lower-cased alphanumericwords with a single space as a delimiter. The Bloom filters
were constructed such that the false positive rate is upperbounded by 1018 . We further verified the low false positive
rate by generating 1M strings, of which zero were found by
the filter.
These Bloom filters let us calculate, given a dataset, thepercentage of 8-grams from that dataset that are also foundin the WebText training set. Table 6 shows this overlap analysis for the test sets of common LM benchmarks. Common
LM datasets’ test sets have between 1-6% overlap with WebText train, with an average of overlap of 3.2%. Somewhat
surprisingly, many datasets have larger overlaps with theirown training splits, with an average of 5.9% overlap.
Our approach optimizes for recall, and while manual inspection of the overlaps shows many common phrases, there aremany longer matches that are due to duplicated data. This is
not unique to WebText. For instance, we discovered that thetest set of WikiText-103 has an article which is also in the
training dataset. Since there are only 60 articles in the test
set there is at least an overlap of 1.6%.4 Potentially moreworryingly, 1BW has an overlap of nearly 13.2% with its
own training set according to our procedure.
For the Winograd Schema Challenge, we found only 10
schemata which had any 8-gram overlaps with the WebText
training set. Of these, 2 were spurious matches. Of theremaining 8, only 1 schema appeared in any contexts that4

A significant portion of additional overlap is due to editors
reusing some paragraphs across multiple articles with a shared
theme such as various battles in the Korean War.

On LAMBADA, the average overlap is 1.2%. GPT-2 performs about 2 perplexity better on examples with greaterthan 15% overlap. Recalculating metrics when excluding
all examples with any overlap shifts results from 8.6 to 8.7
perplexity and reduces accuracy from 63.2% to 62.9%. This
very small change in overall results is likely due to only 1
in 200 examples having significant overlap.
Overall, our analysis suggests that data overlap between
WebText training data and specific evaluation datasets provides a small but consistent benefit to reported results. However, for most datasets we do not notice significantly larger
overlaps than those already existing between standard training and test sets, as Table 6 highlights.
Understanding and quantifying how highly similar text impacts performance is an important research question. Betterde-duplication techniques such as scalable fuzzy matching
could also help better answer these questions. For now, we
recommend the use of n-gram overlap based de-duplication
as an important verification step and sanity check during thecreation of training and test splits for new NLP datasets.
Another potential way of determining whether the performance of WebText LMs is attributable to memorization isinspecting their performance on their own held-out set. As
shown in Figure 4, performance on both the training andtest sets of WebText are similar and improve together asmodel size is increased. This suggests even GPT-2 is still
underfitting on WebText in many ways.
GPT-2 is also able to write news articles about the discoveryof talking unicorns. An example is provided in Table 13.

5. Related WorkA significant portion of this work measured the performanceof larger language models trained on larger datasets. ThisLanguage Models are Unsupervised Multitask Learners

improved the RNN based fine-tuning approaches of (Dai& Le, 2015). (Conneau et al., 2017a) studied the transfer
performance of representations learned by natural language
inference models and (Subramanian et al., 2018) exploredlarge-scale multitask training.
(Ramachandran et al., 2016) demonstrated that seq2seq models benefit from being initialized with pre-trained language
models as encoders and decoders. More recent work has
shown that LM pre-training is helpful when fine-tuned fordifficult generation tasks like chit-chat dialog and dialog
based question answering systems as well (Wolf et al., 2019)(Dinan et al., 2018).

6. Discussion

Figure 4. The performance of LMs trained on WebText as a function of model size.

is similar to the work of Jozefowicz et al. (2016) whichscaled RNN based language models on the 1 Billion Word
Benchmark. Bajgar et al. (2016) also previously improved
results on the Children’s Book Test by creating a much larger
training dataset out of Project Gutenberg to supplement thestandard training dataset. Hestness et al. (2017) conducteda thorough analysis of how the performance of various deeplearning models changes as a function of both model capacity and dataset size. Our experiments, while much noisieracross tasks, suggest similar trends hold for sub-tasks of an
objective and continue into the 1B+ parameter regime.
Interesting learned functionality in generative models
has been documented before such as the cells in an
RNN language model performing line-width tracking andquote/comment detection Karpathy et al. (2015). More inspirational to our work was the observation of Liu et al.
(2018) that a model trained to generate Wikipedia articles
also learned to translate names between languages.
Previous work has explored alternative approaches to filtering and constructing a large text corpus of web pages, suchas the iWeb Corpus (Davies, 2018).
There has been extensive work on pre-training methods
for language tasks. In addition to those mentioned in the
introduction, GloVe (Pennington et al., 2014) scaled word
vector representation learning to all of Common Crawl. An
influential early work on deep representation learning fortext was Skip-thought Vectors (Kiros et al., 2015). McCannet al. (2017) explored the use of representations derived frommachine translation models and Howard & Ruder (2018)

Much research has been dedicated to learning (Hill et al.,2016), understanding (Levy & Goldberg, 2014), and critically evaluating (Wieting & Kiela, 2019) the representationsof both supervised and unsupervised pre-training methods.
Our results suggest that unsupervised task learning is anadditional promising area of research to explore. Thesefindings potentially help explain the widespread success of
pre-training techniques for down-stream NLP tasks as weshow that, in the limit, one of these pre-training techniques
begins to learn to perform tasks directly without the needfor supervised adaption or modification.
On reading comprehension the performance of GPT-2 iscompetitive with supervised baselines in a zero-shot setting.
However, on other tasks such as summarization, while itis qualitatively performing the task, its performance is still
only rudimentary according to quantitative metrics. Whilesuggestive as a research result, in terms of practical applications, the zero-shot performance of GPT-2 is still far fromuse-able.
We have studied the zero-shot performance of WebText
LMs on many canonical NLP tasks, but there are many additional tasks that could be evaluated. There are undoubtedly
many practical tasks where the performance of GPT-2 isstill no better than random. Even on common tasks that weevaluated on, such as question answering and translation,
language models only begin to outperform trivial baselines
when they have sufficient capacity.
While zero-shot performance establishes a baseline of thepotential performance of GPT-2 on many tasks, it is notclear where the ceiling is with finetuning. On some tasks,
GPT-2’s fully abstractive output is a significant departurefrom the extractive pointer network (Vinyals et al., 2015)
based outputs which are currently state of the art on manyquestion answering and reading comprehension datasets.
Given the prior success of fine-tuning GPT, we plan to investigate fine-tuning on benchmarks such as decaNLP and
GLUE, especially since it is unclear whether the additional

Language Models are Unsupervised Multitask Learners

training data and capacity of GPT-2 is sufficient to overcome the inefficiencies of uni-directional representations
demonstrated by BERT (Devlin et al., 2018).

7. Conclusion
When a large language model is trained on a sufficiently
large and diverse dataset it is able to perform well across
many domains and datasets. GPT-2 zero-shots to state of
the art performance on 7 out of 8 tested language modeling datasets. The diversity of tasks the model is able toperform in a zero-shot setting suggests that high-capacity
models trained to maximize the likelihood of a sufficiently
varied text corpus begin to learn how to perform a surprising
amount of tasks without the need for explicit supervision.5

Acknowledgements
Thanks to everyone who wrote the text, shared the links,
and upvoted the content in WebText. Many millions ofpeople were involved in creating the data that GPT-2 wastrained on. Also thanks to all the Googlers who helped us
with training infrastructure, including Zak Stone, JS Riehl,
Jonathan Hseu, Russell Power, Youlong Cheng, Noam
Shazeer, Solomon Boulos, Michael Banfield, Aman Gupta,
Daniel Sohn, and many more. Finally thanks to the people
who gave feedback on drafts of the paper: Jacob Steinhardt,
Sam Bowman, Geoffrey Irving, and Madison May.

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Language Models are Unsupervised Multitask Learners

8. Appendix A: Samples

8.3. Diversity

8.1. Model capacity

Table 12 shows multiple completions of the same random WebText
test set context, showing the diversity of completions with standard
sampling settings.

To complement the reported perplexity gains of bigger LMs on
WebText show in Figure 4, Tables 7 through 11 show side-by-side
completions of the smallest WebText LM and GPT-2 on random
unseen WebText test set articles.

8.2. Text Memorization
We observe some memorizing behavior in GPT-2 on longer strings
that are repeated many times in the dataset such as famous quotes
or speeches. For example, when conditioned on the first sentence
and a half of the Gettysburg Address (which occurs approximately
40 times throughout WebText), an argmax decode from GPT-2
recovers the speech. Even when sampling without truncation, we
find that the model copies the speech for awhile before drifting,albeit in a similar style. It typically drifts within 100-200 tokens,and displays widening diversity once it drifts.
To quantify how often exact memorization shows up in samples,
we generated samples from GPT-2 conditioned on WebText test
set articles and compared the overlap rates of GPT-2’s generations
to the overlap rates of the ground-truth completions. The results ofthis analysis are shown below and suggest that GPT-2 repeats text
from the training set less often then the baseline rate of held-out
articles.

Figure 5. CDF of percentage 8-gram overlap with WebText training set, for both WebText test set and samples (conditioned on
WebText test set, with top-k truncated random sampling withk = 40). Most samples have less than 1% overlap, including over
30% of samples with no overlap, whereas the median for test set is2.6% overlap.

8.4. Robustness
Table 13 shows the previously mentioned talking unicorns news
article. We find the model to be capable of handling out of distribution contexts, but the quality of these samples is generally
lower.

Language Models are Unsupervised Multitask Learners

Context (WebText test)
Outfit 1: TypicalThis pairing was the first outfit I thought of when I bought the shoes. It’s like a summer version of thisJake Grantham outfit; in fact, my shoes are close to the colors of his Nike Racers! Instead of a heavy Harris Tweed
jacket and denim shirt, I’m wearing a cotton DB jacket and and a linen shirt. Both fabrics (in these colors) are an
absolute must for summer, as they go with both dark and and light pants! As you can see, they pair wonderfully
with the dark jeans and shoes. It’s a pseudo menswear/prep outfit.
Overall, this is a very casual outfit which is why I paired my sneakers with it. I’m not about wearing afull wool suit with sneakers (as GQ shows a lot) but I’m definitely open to keeping things casual, like this cotton
DB. Casual fabrics are key to pulling off your sneakers in a dressed down menswear outfit. I’d even suggest towear these sneakers with a khaki chino suit or a white linen suit. Just be sure to ditch the tie or wear a tee or polo;
wearing a tie with sneakers is a bit too much
Small model completion
GPT-2 completion.
for me!
Outfit 2: High End

Outfit 2: Casual Jacket

This outfit was just in the eye of the storm. It’s ahybrid of what ASICS does with streetwear (like J. Crew)
and what J. Crew does with casual pieces that are a bit
more traditional. Again, as I mentioned before, it’s a low
budget item and they can be very expensive. These willdefinitely be an issue if you’re trying to work as a casualsneakermaker, and that’s OK but don’t hesitate if you
want to try the lower price versions of their outfits!

I know that some people might be opposed to wearing
sneakers in a turtleneck, but I wanted to be true to myself,
so I went with a slim fitting turtleneck in a color moresimilar to my favorite color of the day. Overall, it’s aclassic turtleneck, with nothing too flashy. I did swap myshoes for these ASICS Tiger Killshots and I wish I hadn’t
did that. The shoe itself is very comfortable, however,I found that wearing them in these sneakers made myfeet look a bit larger. I’d wear them with denim, chinos,
whatever, but would never recommend wearing themalone. There are just too many variables involved.

This version features a very low cut-cut neckline(which is not a bad thing), slightly longer legs, and a pairof long legs to keep things nice. My preferred color ofcolor these items are blue-gray (which is my first colors,
as they are a light white), or black (which is my favorite
of my designs). As always, my pick of colors from thisstore have nothing to do with that other than the design. For a high end, I would recommend this to everyone!
Outfit 3: High Light
This was a ”high light” look while I had a chance
to get some color. I think the color is based on

Outfit 3: DressThis is the final outfit I wore the ASICS Tiger
Killshots. This version of the ASICS is a much more
modern and streamlined version. The shoe has the mostmodern and minimal design that I can think of! With a lotof black, these sneakers look very cool. They’ll definitely
be very comfortable for summer.
To me, wearing them with a suit is the easiest way
to have a good pair of sneaker shoes. That’s pretty much
it! IfTable 7. Random unseen contexts (top), and non-cherry-picked completions from both the smallest (left) and largest (right) models.
Contexts are 768 tokens, with approximately 256 tokens worth of paragraphs shown. Completions are 256 tokens and fully shown. Top-k
random sampling with k = 40 was used for generation.

Language Models are Unsupervised Multitask Learners

Context (WebText test)
Some of the most glorious historical attractions in Spain date from the period of Muslim rule, including The
Mezquita, built as the Great Mosque of Córdoba and the Medina Azahara, also in Córdoba and now in ruins but
still visitable as such and built as the Madinat al-Zahra, the Palace of al-Andalus; and the Alhambra in Granada, asplendid, intact palace. There are also two synagogues still standing that were built during the era of Muslim Spain:
Santa Marı́a la Blanca in Toledo and the Synagogue of Córdoba, in the Old City.
Reconquista and Imperial era [ edit ]Small model completion

GPT-2 completion

The era of Muslim Spain is very different from that of The Reconquista (literally, ”The return to the country”)
other parts of the world, with a rather extensive medieval of 1092 and 1095 saw the establishment in the Iberian
history. While the Spanish Empire existed during the peninsula of a united kingdom of Castile and Aragon insecond half of the 9th century BC it was quite slowly which a Muslim dynasty would exist. This was the lasttransformed to a small, secularized empire by 1150 A.D., time in Europe where Muslim rule would be considered
in a much more prosperous and diverse state. In 1050 CE ”native” and the last occasion where Christian-inflamed
the emperor of Naples, at least partially in characterised by and organized conflicts would make themselves known ina series of wars and invasions from the north-western coast Europe.
to the western coast of the region (e.g., on the Danube
River which extended all the way from Gibraltar into the The reign of Muslim Moors in Spain is often resouth of Spain, but was quickly destroyed on the same ferred to, especially among non-Muslims, as the
day by the Roman army), assumed the title of Emperor ”Conquest of Granada” and Spain is sometimes referredof Naples. He made a large contribution over the last few to as Spain in ”Granada”. The last years of Muslim ruledecades to restore and maintain the empire, the first of were followed by the Spanish Reconquista where thewhich to the west. His successors were Ferdinand, who Muslims were driven or compelled out of the Iberian
took power from the Papal Throne in 1148, while the first Peninsula with the victory of Ferdinand IX. in the Battle
imperial successor was King Alfred II of Sweden. The of Poitiers in March 1189 and the conquest of Jerusalem
empire was again made one of the few independent states in 1187 by Saladin.
in the European Continent and although no more than 200
million people lived on its territory during this period the The Reconquista period in Spain came to an end
people had much to say to the Emperor. From 1720 on the when the Moors retreated north. However the Moorish
Muslims made up half the population of Spain.
rule would not be fully replaced by the Christian rule until
the Reconquista era resumed when the Reconquista lasted
from 1229 to 1492.
The last Muslim state in Spain, Granada, was conquered by the
Table 8. Random unseen contexts (top), and non-cherry-picked completions from both the smallest (left) and largest (right) models.
Contexts are 768 tokens, with approximately 256 tokens worth of paragraphs shown. Completions are 256 tokens and fully shown. Top-k
random sampling with k = 40 was used for generation.

Language Models are Unsupervised Multitask Learners

Context (WebText test)
Pinky
The pink ghost’s AI is designed to ”feel” opposite of the red ghost’s behavior. Pinky actually attempts to
get out in front of Pac-Man. This is accomplished by setting the target 4 tiles ahead of Pac-Man’s current location in
the direction that Pac-Man is travelling. One exception to this is when Pac-Man is traveling up. Due to an overflow
bug in the code, the calculation includes a left offset equal to the expected up offset.
The use of Pac-Man’s expected position allows the player to exploit the navigation code for Pinky. This was mostoften seen in situations where Pac-Man and Pinky are in close proximity to each other. For example, if they were
headed toward one another, once they are less than 4 tiles apart, the target tile is now behind Pinky. If he encounters
an intersection while in this configuration, he will attempt to double-back (by turning) in order to reach the target tile.
Player’s would often perform what was referred to as a ”head fake” by changing directions rapidly justas Pinky was approaching an intersection. By displacing the target tile just as Pinky
Small model completion
GPT-2 completion
was coming to the left, they would get the ”correct” was about to cross the intersection, Pac-Man would bedirection.
able to dodge the ghosts’ projectiles and return to the safe
location of the safe house.
If the location is actually farther from what PacMan was at, the player’s will not respond to the ghost’s Buster
movement, and the ghost will instead return to the player’s
current location. This is because Pac-Man does not move The yellow ghost’s AI is specifically designed toby turning.
try to avoid Pac-Man from leaving the safe house. The
player must press the SPACE bar to reveal the safe
The ghost will have to go to another location of house’s doors, then go into them to find the yellow ghost
some kind to return where he began, and this is achieved hiding in the next room.
in many ways. It will often simply leave the location, as
for example if Pac-Man did jump off a cliff, he would The player must also note that the ghost will not
return to the spot where he was before vanishing into attempt to exit the safe house if it sees Pac-Man alreadyspace. There is a good number of possibilities these ghost there. In fact, the ghost will not attempt an exit in the firstpaths may be possible, but the most obvious ones are if place unless they’re already in the safe house.
the player wants to avoid getting caught up in the game,with a goal as easy as keeping Pac-Man in the game for These two behaviors are based on the fact that the
1/3 as long as he was.
player does not always attempt to reach the safe house
before Pac-Man (or Blinky).
Chasing
The player must also beware of this glitch if a
In Pac-Man’s case, this would be similar to how ghost (or another player) is already in the safe house
Pac-Man can ”catch up” in a fight.
and attempting to get out as soon as Pac-Man or Blinky
is gone. At this point, the ghost will attempt to exit
A ghost could chase through enemies. This is use- the safe house in a similar manner as it is in ”Chase” mode.
ful for many reasons, both for Pac-Man and his AI.
Unlike most Ghost games, this ghost simply travels in the Pac-Man
direction from
There are some ghosts that follow Pac-Man. These ghosts
areTable 9. Random unseen contexts (top), and non-cherry-picked completions from both the smallest (left) and largest (right) models.
Contexts are 768 tokens, with approximately 256 tokens worth of paragraphs shown. Completions are 256 tokens and fully shown. Top-k
random sampling with k = 40 was used for generation.

Language Models are Unsupervised Multitask Learners

Context (WebText test)
Corporal Michael P. Goeldin was an unskilled laborer from Ireland when he enlisted in Company A in November
1860. Goldein survived the war. Corporal Patrick O’Neal, also from Ireland, first enlisted in 1854 and served with
Company L, 3d U.S. Artillery, in Oregon. He returned to the East Coast and enlisted in the company in 1860.
O’Neal served until 1874, when he was named superintendent of the National Cemetery at Willets Point, New York.
Corporal Benjamin Browne was a shoemaker from Orange County, New York. In August 1862, he enlisted in the
newly formed 124th New York Volunteers, and was one of sixty-one men who transferred into Company A that
October. Browne reenlisted in the company in February 1864 while it was camped at Brandy Station. He returned
to civilian life after completing his enlistment in 1867.
On 10 June, Artificer William Collins was promoted to corporal, probably to fill a combat leadershipvoid for the crossing of the James River. Collins’s service record does not reflect the qualities he demonstrated toearn this promotion, but he had obviously overcome some serious problems. Born in Sacketts Harbor, New York,
Collins enlisted in the company in December 1853 at the age of twenty-two, and reenlisted in December 1858. Justa month before the war began in April 1861, Collins went ”over the hill” and was not caught until three years later.
Returned to the company on 22 March 1864, he was tried
Small model completion
GPT-2 completionon military charges and was discharged from the U.S. in June of that year. Sentenced to be shot for desertion, he
Military. He returned to the company, and was assigned remained on active duty.
to Division of Internal Affairs during the Civil War.
Captain James J. Dall was born in Virginia in 1829 during
As an engineer, Collins also had training in engi- the Revolution and joined his father in the Army in 1836.
neering from his native New York. After graduate studies He served with the 2d Virginia Infantry until 1845, whenin the Union College of Engineering, he was employed he went to the Western Reserve Regiment; and, on his
in the United States Army for two years at the same discharge, he reenlisted with Company I, 25th New York
time. There he worked under Captain Daniel Pfeiffer Volunteers (which in 1845 numbered about 4,500 men).
and was promoted to colonel in May 1870, three years One of his brothers, James, served with his company
after Captain Pfeiffer’s enlistment. Collins returned in the same capacity in the same brigade. While thehome to England after completing his first year in the regiment remained in Connecticut through 1846, CaptainFirst Division to serve the next two years in the Army Dall served with Company I at various times before
Corps of Engineers, and by his second year, he began to his discharge. A veteran of the Mexican War, he had
experience his service duty.¡—endoftext—¿MOSCOW, served two years on the staff of Brigadier General John J.
July 5 (Reuters) - U.K.-based Russian state media and Sullivan at San Antonio. During the Peninsula Campaign
government sources and experts say Moscow has sought of 1863, he commanded a company of twenty-three andto downplay the ”military buildup” of the Syrian oppo- was in charge of the battery of fifty-four heavy mortars
sition while maintaining support for President Donald and the gunboat Pinta of the Battery, a gunboat andTrump’s plan to build a wall along the U.S.-Mexico several other boats. Captain Dall was on active duty withborder, calling it a ”military coup”.
Company I in the fall of 1865. Two years later, he waspromoted to second lieutenant.
U.S.-led Syria war veteran and Syria envoy Michael
Flynn (R), right, gestures with U.S.-based Syrian political Captain John A. O’
analyst Ahmet Koryat, with
Table 10. Random unseen contexts (top), and non-cherry-picked completions from both the smallest (left) and largest (right) models.
Contexts are 768 tokens, with approximately 256 tokens worth of paragraphs shown. Completions are 256 tokens and fully shown. Top-k
random sampling with k = 40 was used for generation.

Language Models are Unsupervised Multitask Learners

Context (WebText test)
Xmonad, Xresources, and Fonts
Xresources can be an absolute pain (they were for me). So, this a bit of help:
First of all, the way that fonts are generally handled in Xmonad is through XFT . Xft is the X FreeType
Interface library and is a library that handles the actual rendering of fonts in Xmonad/urxvt (Xresources specifies
a bunch of resources to things that launch under the X window manager. Settings for individual programs are
specified in Xresources like so: Urxvt.background:background settins here ).
Anyway, fonts are set using this syntax in Xresources :urxvt*font:xft:your font name goes here:size=the size of the font goes here,xft:fall-back font 1 goes here
So, thats the most basic part of fonts in urxvt specified via Xresources.
Fixing /.ssh/ Permissions in Cygwin
In Cygwin on Windows I found that I could not set the permissions of my /.ssh/ folder to be 0600, as isrequired for ssh to allow you to use keys. The symptom I had was that I no matter what I did, it always modfied theowner and the group
Small model completion
GPT-2 completion
was set to /.ssh/ , which was the way things were. This , making these files read-only. I tried just starting ssh
could not be fixed completely. I found I could make that and using a program like passwd which modifies themuch more workable with just typing the username with owner/group to 0644 permissions, but it didn’t work. It
your mouse then trying to set permissions to be ”0600” was annoying but not nearly as bad as it could be, justfor the group, which is what my system is now configured annoying to have to fiddle with permissions.
to do.
So I decided to do this as the reverse:
However, as of Cygwin 7 on Linux I have foundthat doing so is now ”unnecessary” for my system! I also For each .ssh folder in your Cygwin directory, set
installed a package called chroot. It does that by allowing the permission of each file and directory to 2644. Then
you to install/upgrade to your system directory.
start ssh with: ssh-add /.ssh/
So, as of Windows 8 and up, installing that can require chroot, so I tried and tried and found that it wasn’t
so bad when installing the package on Linux and thenuninstalling it. As of my last write-up on Cygwin, thescript just does its job (the sudo commands do the rest), if
you try it you will have to log the change.

The first time you connect, your permissions of
the /.ssh folder that you just had in Cygwin will be
set to 0600. Then every time you connect again, yourpermissions will change to 0644.

If that wasn’t confusing enough, this is what I tried andjust went back to my /.ssh/ directory and the chroot script.
I found I was finally running out of permissions (because
i forgot to create a symlink to ssh from the file system andThese are made in my .xsessionrc :Makefile for Xresources as used in /.xsessionrc.xprofile: .xsession-errors: color=””For example:.xprofile: color=blue
As the colors are stored in a separate file, the color in your/.xsession-errors will look like cyan instead of blue.
This is mostly because, as of now, only the color
is assigned to your

Table 11. Random unseen contexts (top), and non-cherry-picked completions from both the smallest (left) and largest (right) models.
Contexts are 768 tokens, with approximately 256 tokens worth of paragraphs shown. Completions are 256 tokens and fully shown. Top-k
random sampling with k = 40 was used for generation.

Language Models are Unsupervised Multitask Learners

Context (WebText test)
Aaron loves mint chocolate cake, but he requires that it be paired with mini chocolate chips, so I threw some ofthose in between the layers. I also had a few Peppermint Jo Jos on hand so I crushed them up and threw some ofthose in along with some crushed meringue cookies because, why not? It’s a total smorgasbord of minty chocolatechippy cookie crunchy goodness. I didn’t measure how much of each topping I used, but after I tasted the finishedproduct, I wish I had added more. You can add anything you want- crushed candy canes, peppermint bark, etc. And
don’t be afraid to use a heavy hand. Texture = good.
If you don’t have 7-inch cake pans, you can get 3 shorter 8-inch layers out of thisGPT-2 Completion 1
GPT-2 Completion 2
GPT-2 Completion 3
recipe. I made the longer version, recipe. If you do, and you know recipe, which will likely yield about
then used the pan for a layer of how to make that cake, then your the same amount of cake.
buttercream frosting and stuck 1/3 life will never be the same.
of it into the fridge for a frosting
ChocolateButtermilk
Caketopper. Just make sure you have all I have two very simple rules Print Chunks of chocolate cake,of this frosting prepared earlier than when it comes to cookie crumbs coated in buttermilk and topped
you make this cake and you won’t or chocolate chips. 1) When I buy with crunchy chopped chocolate,have to wait on it as your egg whites raw sugar, I do not use it until it’s drizzled with chocolate sauce.
sit on the bottom of your mixing cooled down and has at least half a Simple but a nice change frombowl.
teaspoon of sugar on it. That’s my chocolate cake! Author: Momma
rule. And 2) If I have a recipe that Made Ingredients For the chocolate
You want the egg whites whipped calls for something and I want to buttermilk cake 1 1/2 cup unsalted
to stiff peaks? Then put your cake use it in a recipe, I do not substitute butter , room temperaturedish over a pot of simmering water it with something else on-line. Likeand heat it up until it’s just barely this.
1 1/2 cup granulated sugar
warm. It doesn’t take more than 3-5
3 large eggs plus 1 egg yolk For
minutes; just enough to get it started I found this really cute card the chocolate glaze 1/3 cup cocoawith cute little kittens on
powder
1 3/4 cups powdered sugar
6 ounces semis
GPT-2 Completion 4

GPT-2 Completion 5

recipe.

recipe.

Meringue Cookies

My 2 failures at Christmas morning
were not due to poor frosting skills.
That was another success story.
The cake was beautifully moist,
and well, just a beautiful cake. It’s
got very little air in it or moisture,
but all the chocolate and mint was
perfectly blended together.

1 3/4 cup butter, softened
1 cup sugar
1 egg yolk
3 T. heavy cream
3 1/2-4 cups flour
pinch of salt
Peppermint-Jojo Topping
1 1/4 cups powdered sugar
1 cup chopped pecans
1/2 cup finely chopped mint leaves
1/2 cup chopped fresh mint (about
1/2 sheet)
1 tsp. peppermint extract
1/4 tsp. sea salt
pinch of sea

One thing that made me cringe a
bit was that all those ingredientsegg yolks, sugar, melted butter,chocolate chips, melted chocolate,and mint- had to be mixed right
into the cake batter, which issuper time-consuming. A friend
suggested that if I put the batter in a
separate bowl, I

GPT-2 Completion 6
recipe, which will give you about
6-9 servings of delicious chocolate
cake.
To prevent your layers
from sticking together, I used my
8-inch round tart pan, lined it withparchment paper, then cut up 4
7-inch round cakes from it andsandwiched the layers between
them (this also worked well forthe 1-layer chocolate cake as well).
When you’re ready to bake thiscake, remove the parchment paper,
preheat oven to 350 degrees andbake for about 30 – 40 minutes,
until the top is golden and a tester
comes out clean.
ChocolateButtermilk
Cake with Peppermint Jo

Layer

Table 12. Non-cherry-picked completions from GPT-2 generated from the same context (from WebText test). Context is 384 tokens(shown truncated), and generations are 128 tokens. Top-k random sampling with k = 40 was used for generation.

Language Models are Unsupervised Multitask Learners

Context (human-written): In a shocking finding, scientist discovered a herd of unicorns living
in a remote, previously unexplored valley, in the Andes Mountains. Even more surprising to theresearchers was the fact that the unicorns spoke perfect English.
GPT-2: The scientist named the population, after their distinctive horn, Ovid’s Unicorn. Thesefour-horned, silver-white unicorns were previously unknown to science.
Now, after almost two centuries, the mystery of what sparked this odd phenomenon is finally solved.
Dr. Jorge Pérez, an evolutionary biologist from the University of La Paz, and several companions, were exploring the Andes Mountains when they found a small valley, with no other animals
or humans. Pérez noticed that the valley had what appeared to be a natural fountain, surrounded by
two peaks of rock and silver snow.
Pérez and the others then ventured further into the valley. “By the time we reached the topof one peak, the water looked blue, with some crystals on top,” said Pérez.
Pérez and his friends were astonished to see the unicorn herd. These creatures could beseen from the air without having to move too much to see them – they were so close they could touch
their horns.
While examining these bizarre creatures the scientists discovered that the creatures also
spoke some fairly regular English. Pérez stated, “We can see, for example, that they have a common‘language,’ something like a dialect or dialectic.”
Dr. Pérez believes that the unicorns may have originated in Argentina, where the animals
were believed to be descendants of a lost race of people who lived there before the arrival of humans
in those parts of South America.
While their origins are still unclear, some believe that perhaps the creatures were created
when a human and a unicorn met each other in a time before human civilization. According to Pérez,“In South America, such incidents seem to be quite common.”However, Pérez also pointed out that it is likely that the only way of knowing for sure if
unicorns are indeed the descendants of a lost alien race is through DNA. “But they seem to be able tocommunicate in English quite well, which I believe is a sign of evolution, or at least a change insocial organization,” said the scientist.
Table 13. Conditional generation on an out-of-distribution context by GPT-2. Cherry pick of 10 samples generated with k = 40.

Language Models are Unsupervised Multitask Learners

Article: Prehistoric man sketched an incredible array of prehistoric beasts on the rough limestone walls of a cave inmodern day France 36,000 years ago.
Now, with the help of cutting-edge technology, those works of art in the Chauvet-Pont-d’Arc Cave have been
reproduced to create the biggest replica cave in the world.
The manmade cavern named the Caverne du Pont-d’Arc has been built a few miles from the original site in
Vallon-Pont-D’arc in Southern France and contains 1,000 painstakingly-reproduced drawings as well as around 450
bones and other features...
Cavemen and women sketched an incredible array of prehistoric beasts on the rough limestone walls of a cave
36,000 years ago and now a replica has been created (pictured)...
GPT-2: The original site in Vallon-Pont-D’arc in Southern France is a Unesco World Heritage site and is theoldest known and the best preserved cave decorated byman. The replica cave was built a few miles from the original site in Vallon-Pont-D’Arc in Southern France. The
cave contains images of 14 different species of animals
including woolly rhinoceros, mammoths, and big cats.

Reference: Cave mimics famous Caverne du Pont-d’Arc
in France, the oldest cave decorated by man and thebest preserved. The replica contains all 1,000 paintings which include 425 such as a woolly rhinoceros andmammoths. Minute details were copied using 3D modelling and anamorphic techniques, often used to shootwidescreen images. The modern cave also includes replica
paw prints of bears, bones and details preserved in theoriginal cave.

Article: ‘If you can find my submarine, it’s yours,’ Russian oil billionaire Roman Abramovich once said.
And it seems the oligarch and Chelsea FC owner, whose submarine is just one of the extras that came with his£300million superyacht Eclipse (perfect for getting to shore undetected), is not the only wealthy businessman
splashing out on underwater exploration.
Dubbed Earth’s real ‘final frontier’, the oceans are still so little-explored that billionaires are queuing up to buy
vessels that give them a glimpse of the dramatic seascapes and incredible wildlife of the world’s oceans.
So if you have a spare few million in the bank and want some holiday snaps and Instagram posts that will reallytrump everyone else, you may want to snap up one of these...
Whale of a time: The OrcaSub takes you 2000 feet beneath the surface in two pressurised Perspex viewing domes
for optimum exploration...
GPT-2: The U-Boat Worx submarine can dive to 984 feet(300 metres) and is capable of diving to the bottom of
the ocean. It can be used for diving, snorkelling and evensnorkel diving. The submarine is also equipped with asnorkelling platform.

Reference: Feel like a James Bond villain with the mostadvanced submerged ocean vehicles. Some convert froma yacht into a submarine, and others detached off for a
speedy exploration. Oliver’s Travels offers a Mile Low
package on its submarine, complete with chef and butler
for £175,000 a night.

Article: Amina Ali Qassim is sitting with her youngest grandchild on her lap, wiping away tears with her headscarf.
Only a few months old, this is the baby girl whose ears she desperately tried to cover the night the aerial bombardment
started. She lay awake, she says, in a village mosque on the Yemeni island of Birim, counting explosions as thebaby cried.
It could have been worse though. They could have still been in their house when the first missile landed.
”Our neighbor shouted to my husband ’you have to leave, they’re coming.’ And we just ran. As soon as we left thehouse, the first missile fell right by it and then a second on it. It burned everything to the ground,” Qassim tells us...
GPT-2: Yemen is in the middle of a civil war. Saudi
Arabia is leading the coalition bombing campaign. It’s
been bombing Yemen for more than two months now.

Reference: Amina Ali Qassim’s family sought shelter ina mosque before fleeing Yemen. Thousands like them areboarding boats to sail to Djibouti. Saudi Arabia has beenpounding Yemen in a bid to defeat Houthi rebels.

Table 14. Summaries generated by GPT-2 and reference summaries on the test set of the CNN and Daily Mail dataset.

Language Models are Unsupervised Multitask Learners

English reference

GPT-2 French translation

This re-release, titled The Next Day Extra, was presented
in the form of three disks: the original album, unpublishedstudio sessions and remixes, plus a DVD containing thefour clips that have already been unveiled.

Les nouvelles re-releases, tout en premier disc, nécessairede l’album, un studio session et remixes, plus une DVDde l’écran de quelques clips qui ont été déjà échappés.

French reference

GPT-2 English translation

Un homme expliquait que le fonctionnement de la hernia
fonctionnelle qu’il avait reconnaı̂t avant de faire, le fonctionnement de la hernia fonctionnelle que j’ai réussi, j’ai
réussi.

This release, originally released on three discs: the original album, sessions studio inédites and remixes, a DVD
containing the four clips that were released on the previous
day.

English reference

GPT-2 French translation

One man explained that the free hernia surgery he’d received will allow him to work again.

Un homme expliquait que le fonctionnement de la hernia
fonctionnelle qu’il avait reconnaı̂t avant de faire, le fonctionnement de la hernia fonctionnelle que j’ai réussi, j’ai
réussi.

French reference

GPT-2 English translation

Un homme a expliqué que l’opération gratuite qu’il avait
subie pour soigner une hernie lui permettrait de travaillerà nouveau.

A man told me that the operation gratuity he had beenpromised would not allow him to travel.

English reference

GPT-2 French translation

Speaking to an open government conference in London
via video link, Mr Kerry said: ”There is no question that
the President and I and others in government have actuallylearned of some things that had been happening on an
automatic pilot because the ability has been there, goingback to World War Two and to the very difficult years of
the Cold War, and then, of course, 9/11.”

Le premier conference de l’édition internationale en ligne
sur la vide, le ministre de l’Édition internationale a étévide, lui dit : ”Il n’y a qu’une question que le président
et moi et tous les autres personnes d’une administration
qui a été évident par la fois, par la part de la guerre, par lapart de la guer

French reference

GPT-2 English translation

S’exprimant lors d’une conférence intergouvernementaleà Londres par liaison vidéo, M. Kerry a déclaré: ”Il estindéniable que le Président, moi-même et d’autres membres du gouvernement avons pris connaissance de certaines choses en mode pilote automatique parce que nous
en avions la possibilité, dès la Seconde guerre mondiale etjusqu’aux années difficiles de la Guerre froide, puis biensûr le 11 septembre.”

In a conférence between the United States and London,
Secretary of State John Kerry said: ”It is indeniable that
the President, myself and others of the government havebeen aware of certain certain choices that have been madein the past in order to be able to do certain things in a more
automated way.”

Table 15. English to French and French to English translations generated by GPT-2.

Language Models are Unsupervised Multitask Learners

Context (passage and previous question/answer pairs)
The 2008 Summer Olympics torch relay was run from March 24 until August 8, 2008, prior to the 2008 Summer
Olympics, with the theme of “one world, one dream”. Plans for the relay were announced on April 26, 2007, in
Beijing, China. The relay, also called by the organizers as the “Journey of Harmony”, lasted 129 days and carried
the torch 137,000 km (85,000 mi) – the longest distance of any Olympic torch relay since the tradition was started
ahead of the 1936 Summer Olympics.
After being lit at the birthplace of the Olympic Games in Olympia, Greece on March 24, the torch traveled to the Panathinaiko Stadium in Athens, and then to Beijing, arriving on March 31. From Beijing, the torch was
following a route passing through six continents. The torch has visited cities along the Silk Road, symbolizing
ancient links between China and the rest of the world. The relay also included an ascent with the flame to the top of
Mount Everest on the border of Nepal and Tibet, China from the Chinese side, which was closed specially for the
event.
Q: What was the theme
A: “one world, one dream”.
Q: What was the length of the race?
A: 137,000 km
Q: Was it larger than previous ones?
A: No
Q: Where did the race begin?
A: Olympia, Greece
Q: Is there anything notable about that place?
A: birthplace of Olympic Games
Q: Where did they go after?
A: Athens
Q: How many days was the race?
A: seven
Q: Did they visit any notable landmarks?
A: Panathinaiko Stadium
Q: And did they climb any mountains?
A:
Model answer: Everest
Turker answers: unknown, yes, Yes, yes
Table 16. Selected CoQA completion.

Language Models are Unsupervised Multitask Learners

Context (passage and previous question/answer pairs)
Tom goes everywhere with Catherine Green, a 54-year-old secretary. He moves around her office at work and goes
shopping with her. ”Most people don’t seem to mind Tom,” says Catherine, who thinks he is wonderful. ”He’s myfourth child,” she says. She may think of him and treat him that way as her son. He moves around buying his food,paying his health bills and his taxes, but in fact Tom is a dog.
Catherine and Tom live in Sweden, a country where everyone is expected to lead an orderly life according to rules laid down by the government, which also provides a high level of care for its people. This level of carecosts money.
People in Sweden pay taxes on everything, so aren’t surprised to find that owning a dog means moretaxes. Some people are paying as much as 500 Swedish kronor in taxes a year for the right to keep their dog, whichis spent by the government on dog hospitals and sometimes medical treatment for a dog that falls ill. However, mostsuch treatment is expensive, so owners often decide to offer health and even life for their dog.
In Sweden dog owners must pay for any damage their dog does. A Swedish Kennel Club official explains what this means: if your dog runs out on the road and gets hit by a passing car, you, as the owner, have to pay
for any damage done to the car, even if your dog has been killed in the accident.
Q: How old is Catherine?
A: 54
Q: where does she live?
A:
Model answer: Stockholm
Turker answers: Sweden, Sweden, in Sweden, Sweden
Table 17. Selected CoQA completion.