Context-dependent vs. context-free: performance comparison of grammar-based codes
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
In this paper, we compare the performance of two types of universal data compression algorithms: context-dependent grammar-based (CDG-based) codes and context-free grammar-based (CFG-based) codes. The theoretical comparison of two algorithm is complicated by the following two facts observed: 1) Both CDG-based codes and CFG-based codes are universal for the class of stationary, ergodic sources with a finite alphabet; and 2) When the number of distinct contexts is upper bounded by a fixed number, the upper bounds on worst-case redundancy of CDG-based codes and CFG-based codes against any finite context arithmetic codes are in the same order of O(log log n/ log n). previously, two universal algorithms were compared only on the basis of some individual sequences. It was shown that for any sequential lossless code that is performable on a computer, there exists a sequence that is not compressible by the given code.
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Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it