MétaCan
Menu
Back to cohort
Record W7027350039

Change-Point Detection in Business Cycles using Machine Learning Algorithms

2022· dissertation· en· W7027350039 on OpenAlex

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.

aboutThe title or abstract carries a Canadian signal from the geographic lexicon.
no affNo Canadian affiliation: this work is invisible to an affiliation-only frame.
No Canadian affiliation. An affiliation-only frame, the usual design, would never have seen this work. It is one of the works that make the case for inverting the frame.

Bibliographic record

VenueRepositorio Institucional de la Universidad de Alicante (Universidad de Alicante) · 2022
Typedissertation
Languageen
FieldAgricultural and Biological Sciences
TopicSensory Analysis and Statistical Methods
Canadian institutionsnot available
Fundersnot available
KeywordsFeature selectionRecessionClassifier (UML)Robustness (evolution)Binary classificationTime seriesBusiness cycleModel selectionEnsemble learning
DOInot available

Abstract

fetched live from OpenAlex

Turning points in business cycles are defined as the onset of a recession or an expansion which are quite difficult to be predicted. In this thesis, we approach the problem of turning (change) point detection as the viewpoint of binary classification task. Due to the small ratio of changes to total data (as the number of recessions is relatively low), we face heavily class-imbalance challenge in this problem. We explore a wide variety of machine learning-based solutions for this problem: from base classifier to the multi-step classifier ensemble algorithm as well as a feature selection step. We examined the proposed classification methods on Canadian large dataset. Among different examined methods, the hybrid ensemble method including data sampling followed by a feature selection and multi-step ensemble can predict the Covid19 recession’s changepoints precisely with all the time series available one month ago. Some robustness checks such as the effect of window size on the model performance are also provided. Moreover, excluding the financial crisis from the training set, the method 8 is still able to predict the changepoints in the case of financial crisis precisely, however, in the case of the Covid-19 recession, they were detected one-period late, suggesting importance of financial crisis’ data in detecting Covid-19 change points.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

Full frame distilled prediction

Teacher imitation

Not 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.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesMeta-epidemiology (narrow)
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.785
Threshold uncertainty score1.000

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0010.000
Meta-epidemiology (narrow)0.0010.000
Meta-epidemiology (broad)0.0010.000
Bibliometrics0.0000.002
Science and technology studies0.0010.000
Scholarly communication0.0000.000
Open science0.0010.000
Research integrity0.0010.001
Insufficient payload (model declined to judge)0.0010.000

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.

Opus teacher head0.024
GPT teacher head0.290
Teacher spread0.266 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it