Bibliographic record
Abstract
This is a tutorial paper for Hidden Markov Model (HMM). First, we briefly review the background on Expectation Maximization (EM), Lagrange multiplier, factor graph, the sum-product algorithm, the max-product algorithm, and belief propagation by the forward-backward procedure. Then, we introduce probabilistic graphical models including Markov random field and Bayesian network. Markov property and Discrete Time Markov Chain (DTMC) are also introduced. We, then, explain likelihood estimation and EM in HMM in technical details. We explain evaluation in HMM where direct calculation and the forward-backward belief propagation are both explained. Afterwards, estimation in HMM is covered where both the greedy approach and the Viterbi algorithm are detailed. Then, we explain how to train HMM using EM and the Baum-Welch algorithm. We also explain how to use HMM in some applications such as speech and action recognition.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.005 |
| Meta-epidemiology (narrow) | 0.003 | 0.001 |
| Meta-epidemiology (broad) | 0.002 | 0.002 |
| Bibliometrics | 0.002 | 0.004 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.002 | 0.004 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.003 | 0.004 |
| Insufficient payload (model declined to judge) | 0.054 | 0.027 |
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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".