Update Readme

add details for folder structures and data scheme for common crawl data

README.md

@@ -66,6 +66,161 @@ Each data source was filtered individually with respect to the underlying data.
 ## Global Deduplication
 After the web and curated sources were filtered, all sources globally deduplicated to create TxT360. The tips and tricks behind the deduplication process are included.
 
+## Dataset Structure
+The dataset is organized under the ```data``` directory, with each subdirectory representing a data subset. 
+Below is an overview of the structure and organization of these subsets:
+```
+├── data
+    ├── common-crawl  # data subset
+        ├── CC-MAIN-2013-20  # common-crawl dumps
+            ├── 1-1  # number of duplicates
+                ├── chunk_000_0000.jsonl.gz
+                ├── ...
+            ├── 2-5
+                ├── chunk_000_0000.jsonl.gz
+                ├── ...
+            ├── ...
+        ├── CC-MAIN-2013-48
+            ├── 1-1
+                ├── chunk_000_0000.jsonl.gz
+                ├── ...
+            ├── ...
+        ├── ...
+    ├── dm_math
+        ├── full_data_1
+            ├── 0_11255.jsonl
+            ├── ...
+        ├── full_data_2
+            ├── 10000_11255.jsonl
+            ├── ...
+    ├── arxiv
+        ├── 1-1  # number of duplicates
+            ├── 0_171.jsonl
+            ├── ...
+        ├── 2-5
+            ├── 0_2.jsonl
+            ├── ...
+        ├── ...
+    ├── europarl
+        ├── 1-1  # number of duplicates
+            ├── 0_6.jsonl
+            ├── ...
+        ├── 2-5
+            ├── 0_0.jsonl
+            ├── ...
+        ├── ...
+    ├── ...
+```
+
+### Common Crawl (common-crawl)
+Each subdirectory under ```common-crawl``` corresponds to a specific dump of the dataset. 
+Inside each dump folder, the data is further segmented into buckets based on the number of duplicates identified during deduplication:
+
+- ```1-1```: Contains documents with no duplicates across the dataset.
+- ```2-5```, ```6-10```, ```11-100```, ```101-1000```, ```1001-30000000```: Each contains documents that fall within the respective range of duplicates.
+
+Example path: ```data/common-crawl/CC-MAIN-2013-20/1-1/chunk_000_0000.jsonl.gz```
+
+### DM Math (dm_math)
+The ```dm_math``` subset is divided into two subfolders to comply with the limit of 10,000 files per folder in a HuggingFace Repository:
+
+Example path: ```data/dm_math/full_data_1/0_11255.jsonl```
+
+### Others
+Similar to common-crawl, other curated data subsets, such as arxiv, europal, etc., are organized by the number of duplicates:
+- ```1-1```, ```2-5```, ```6-10```, ```11-100```, ```101-1000```, ```1001-inf```
+
+Kindly note that some data subsets might not include the folder ```1001-inf``` (```1001-30000000``` in ```common-crawl```) or might contain only a few documents in such a folder due to the rarity of documents duplicated more than 1000 times. 
+
+## Data Schema
+
+### Common Crawl (common-crawl)
+The documents in common-crawl follow the schema:
+```python
+{'text': '...',  # texts in the document
+ 'meta': 
+    {
+        'lang': 'en',  # top 1 language detected by fastText model
+        'lang_score': 0.912118136882782,  # language score for the detected language
+        'url': 'http://www.shopgirljen.com/2017/10/lg-celebrates-5-years-of-lg-oled-tv.html',  # the url that raw webpage is scraped from
+        'timestamp': '2024-07-24T00:56:12Z',  # timestamp from Common Crawl raw data
+        'cc-path': 'crawl-data/CC-MAIN-2024-30/segments/1720763518130.6/warc/CC-MAIN-20240723224601-20240724014601-00300.warc.gz',  # the path of the document in the raw Common Crawl
+        'quality_signals':
+            {
+                'url_score': 0.0,
+                'fraction_of_duplicate_lines': 0.0,
+                'fraction_of_characters_in_duplicate_lines': 0.0,
+                'fraction_of_duplicate_paragraphs': 0.0,
+                'fraction_of_characters_in_duplicate_paragraphs': 0.0,
+                'fraction_of_characters_in_most_common_ngram': [[2, 0.03626373626373627],
+                    [3, 0.03296703296703297],
+                    [4, 0.01868131868131868]],
+                'fraction_of_characters_in_duplicate_ngrams': [[5, 0.01868131868131868],
+                    [6, 0.01868131868131868],
+                    [7, 0.01868131868131868],
+                    [8, 0.0],
+                    [9, 0.0],
+                    [10, 0.0]],
+                'fraction_of_words_corrected_in_lines': 0.0,
+                'fraction_of_lines_ending_with_ellipsis': 0.0,
+                'fraction_of_lines_starting_with_bullet_point': 0.0,
+                'fraction_of_lines_with_toxic_words': 0.0,
+                'num_of_lines_with_toxic_words': 0,
+                'num_of_toxic_words': 0,
+                'word_count': 358,
+                'mean_word_length': 5.083798882681564,
+                'num_of_sentences': 19,
+                'symbol_to_word_ratio': 0.0,
+                'fraction_of_words_with_alpha_character': 1.0,
+                'num_of_stop_words': 82,
+                'num_of_paragraphs': 0,
+                'has_curly_bracket': False,
+                'has_lorem_ipsum': False,
+                'orig_text_has_dup_lines': False
+                },
+        'dup_signals': 
+            {
+                'dup_doc_count': 166,  # the number of duplicated documents
+                'dup_dump_count': 57,  # the number of dumps that the duplicated documents are from
+                'dup_details':   # the dump distribution of the duplicated documents
+                    {
+                        '2024-30': 2,
+                        '2024-26': 1,
+                        '2024-22': 1,
+                        ...
+                        }
+                }
+        },
+ 'subset': 'commoncrawl'}
+```
+
+Please note that documents without duplicates, located in folders `*/1-1/`, have an empty `dup_signals` field. 
+Additionally, some documents with duplicates might include an `unknown` entry within the `dup_details`. 
+One example could be:
+```python
+{'text': '...',  # texts in the document
+ 'meta': 
+    {
+        ...
+        'dup_signals': 
+            {
+                'dup_doc_count': 7,
+                'dup_dump_count': 3,
+                'dup_details':
+                    {
+                        'unknown': 4,
+                        '2024-30': 1,
+                        '2024-26': 1,
+                        '2024-22': 1,
+                        }
+                }
+        },
+ 'subset': 'commoncrawl'}
+```
+This occurs because the distribution of duplicates across dumps was not recorded in the early stages of our deduplication process, and only the total count of duplicate documents (`dup_doc_count`) was maintained. 
+Due to the high cost of rerunning the deduplication, we have opted to label these distributions as `unknown` when integrating them with other documents for which duplicate distribution data is available.
+In these cases, the `dup_dump_count` is calculated excluding the `unknown`.
+
 # Citation
 
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