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Forecasting Influenza Hospitalizations Using a Bayesian Hierarchical Nonlinear Model with Discrepancy

T0 review · 3 major / 5 minor · reviewed 2026-08-11 · deepseek-v4-flash

Pith's one-line read A Bayesian two-module scheme with a discrepancy term produces accurate probabilistic forecasts of weekly influenza hospitalizations, beating 19 of 20 non-ensemble FluSight submissions in the 2023-24 season.

desk verdict A useful Bayesian two-component forecasting framework with a real simulation study, but the headline 2023-24 comparison depends on an unstated detail about when the empirical Bayes prior is fit. read the letter →

arxiv 2412.14339 v2 pith:GH6GMWTG submitted 2024-12-18 stat.AP

classification stat.AP MSC 62F1562P1092D30
keywords influenzaforecastingBayesianhierarchicalmodeldiscrepancyprobabilistichospitalizationforecastsFluSightasymmetricGaussianfunctionweightedintervalscore
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper claims that weekly influenza hospitalizations can be forecast reliably by chaining two Bayesian models: a hierarchical model that fits seasonal flu-like-illness (ILI) data with a nonlinear curve plus a systematic discrepancy term, and a regression model that converts forecast ILI into hospitalization counts. Because ILI records go back to 2010 while reliable hospitalization data exist only since 2021, the framework lets the long ILI history drive forecasts of the newer target. In a simulation study the discrepancy-augmented asymmetric Gaussian (ASGD) model gave the lowest weighted interval scores and the closest-to-nominal interval coverage among six models. In the real 2023-24 season, the ASGD NORM2 configuration outperformed 19 of the 20 non-ensemble FluSight submissions by mean log-weighted interval score and showed better calibration than the competitors. If the claim holds, public health agencies get an inexpensive, fast, and competitive probabilistic hospitalization forecast from data that are already collected.

What carries the argument

The load-bearing object is the two-module forecast pipeline joined by a Bayesian cut. Module one is a hierarchical Beta regression for ILI with logit mean $f_{\theta_s}(w)+\gamma_w+\upsilon_{s,w}$, where $f_{\theta_s}$ is either the infectious compartment of an SIR model or the asymmetric Gaussian (ASG) function, a two-piece bell-shaped curve whose rise and fall rates can differ; $\gamma_w$ is a reverse-random-walk discrepancy shared by all seasons and $\upsilon_{s,w}$ is a current-season discrepancy. Module two is the hospitalization model $H_{s,w}=\alpha_{0s}+\alpha_{1s}(\mathrm{ILI}_{s,w}P)+\alpha_{2s}(\mathrm{ILI}_{s,w}P)^2+\phi H_{s,w-1}+\epsilon_{s,w}$, an ARX(1) regression. The modules are fit separately with MCMC, and draws from the ILI posterior predictive distribution are plugged into the hospitalization model to produce forecast quantiles. This machinery carries the argument because it transfers information from thirteen seasons of ILI data to a target with only two seasons of hospitalization data, and the discrepancy terms correct systematic shape errors such as the underprediction of the holiday-week peak that a smooth curve alone would miss.

What would settle it

Refit the ASGD ILI module with log-normal, truncated-normal, and negative-binomial hospitalization error models and rerun the 2023-24 FluSight comparison on exactly the same targets; if any of these alternatives beats ASGD NORM2 or changes its rank by more than one position, the normal-error assumption is load-bearing rather than incidental. A complementary check is to apply the log-scale model that was validated in the simulation to the raw hospitalization data and see whether its interval scores match the paper's real-data results.

Watch

Extended reading notes

Core claim

The paper's central claim is that a two-component Bayesian framework—an ILI module whose logit mean is a nonlinear trajectory function plus a season-shared and a season-specific reverse-random-walk discrepancy term, coupled through a Bayesian cut to an ARX(1) hospitalization module with ILI as a linear or quadratic predictor—produces accurate and well calibrated 1- to 4-week-ahead probabilistic forecasts of state and national flu hospitalizations. The preferred configuration, ASGD NORM2, uses the asymmetric Gaussian function with discrepancy for ILI and a normal-error hospitalization model with a quadratic ILI term. In the 2023 FluSight comparison the authors report that this scheme outperformed all but one of the 20 non-ensemble competing models on the log-weighted interval score, and that the discrepancy component was particularly valuable around the holiday-week ILI peak. The paper intends these results as evidence that long ILI records can compensate for the short hospitalization record and that careful discrepancy modeling, not a more complex mechanistic model, is what most improves forecast skill.

Load-bearing premise

The real-data evaluation assumes that the normal-error ARX model on raw hospitalization counts, with negative forecast draws truncated to zero, is adequate for the 2023-24 season even though the simulation study validated a log-transformed version of the model; if that error specification is misspecified, the reported forecast scores and calibration may not reflect the method's true performance.

Editorial extensions

If this is right

  • State and national influenza hospitalization forecasts can exploit ILI data back to 2010, sidestepping the short hospitalization record.
  • Adding a discrepancy term to the ILI curve improves forecast skill and calibration, especially for forecasts that straddle the holiday-week ILI peak.
  • Fitting the ILI and hospitalization modules separately and coupling them through a Bayesian cut is faster, more stable, and more accurate in this application than fitting the joint model.
  • A relatively simple two-stage regression scheme can compete with specialized FluSight forecast submissions, including mechanistic and machine-learning models.
  • The residual gap to the best FluSight model points to spatial structure as the next improvement, since the one model that outperformed ASGD NORM2 was a spatial model.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • A natural stress test the paper does not run is a season with an early or late ILI peak: the discrepancy random walk is trained on historical holiday-week patterns, so a shifted peak could erode the forecast gains.
  • If the normal-error mismatch between the simulation and real-data analyses is real, switching to a count-valued or log-scale hospitalization model that preserves calibration could make the FluSight ranking more robust.
  • The same two-module template should transfer to other respiratory diseases that have long syndromic surveillance and short hospitalization records, since nothing in the structure is influenza-specific.
  • Spatially informed pooling of the ILI or hospitalization modules is the most direct route to closing the small gap to the winning FluSight model and to improving forecasts for states like Montana, where ASGD NORM2 underperformed.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 5 minor

Summary. This paper proposes a two-component Bayesian framework for probabilistic forecasting of weekly influenza hospitalizations in the US. The first component is a hierarchical nonlinear model for influenza-like illness (ILI), using either an SIR compartmental model or an asymmetric Gaussian (ASG) function, with an optional reverse-random-walk discrepancy term. The second component is an ARX(1) model in which hospitalizations are regressed on ILI forecasts, with the two modules combined in the style of a Bayesian cut. The authors evaluate the framework in a leave-one-season-out simulation study of log-hospitalizations and in a real-data analysis of 2023-24 state and national hospitalization forecasts, comparing their ASGD NORM2 model against 20 non-ensemble FluSight submissions. The central claim is that the proposed approach outperformed all but one of those 20 models over the 2023 season.

Significance. If the central claim survives scrutiny, the paper provides a practically useful and computationally feasible forecasting framework that leverages the longer ILI record to forecast the newer hospitalization target. The evaluation has notable strengths: it uses proper scoring rules, compares against external FluSight benchmarks rather than only internal baselines, and reports shared-target relative scores (RLWIS) to mitigate missing-forecast artifacts. The simulation study is genuinely out-of-sample through the leave-one-season-out design. However, two load-bearing issues currently prevent the headline claim from being accepted at face value: the timing of the empirical Bayes prior for the ASG baseline parameter is not specified relative to the forecast season, and the simulation study validates a log-hospitalization model while the real-data evaluation uses a normal model on raw counts with truncation. These concerns are fixable but require additional analysis or explicit clarification.

major comments (3)
  1. [Section 3.6 and Section 5] The out-of-sample validity of the 2023 FluSight comparison is not established because the empirical Bayes prior for the ASG parameter lambda_s is described as being centered at the mean of MLEs 'across all seasons' without stating whether the 2023 season is included or whether the 2023 MLE, if used, is computed only from data available at each forecast week. Section 3.6 also states that the prior variance was set so that the prior was 'tight around the mean' and that this choice 'led to improved mixing of posterior draws and better forecasts,' but the text does not say whether this tuning was carried out on the 2023 forecast targets. If the full 2023 ILI trajectory enters the prior, then every forecast in Section 5 is informed by future observations, which would invalidate the comparison against the 20 FluSight models. The authors must state precisely which seasons and which data windows are used to construct this prior, and if the full 2023 season enters, rerun the analysis with a prior constructed only from seasons and weeks preceding each forecast date.
  2. [Section 4 versus Sections 3.8 and 5] The simulation study validates a different hospitalization model from the one used in the real-data headline analysis. Section 4 states that 'we simulated log-hospitalizations' and that the data-generating parameters were estimated by fitting model (6) after log-transforming hospitalizations, whereas Section 3.8 describes a normal-error model on raw hospitalization counts whose negative predictive draws are truncated to zero for the Section 5 analysis. The LOSO simulation therefore provides evidence for the log-scale version of the model, but it does not directly support the adequacy of the normal-on-raw-counts model with truncation that produces the reported 2023 forecasts. Without a simulation or calibration check for that exact error specification, the favorable scores of ASGD NORM2 in Table 2 could be driven by an error model that the simulation never tested. The authors should either rerun the simulation under the normal/truncated specification used in Section 5 or add an explicit demonstration that the two error specifications lead to equivalent forecast performance for the 2023 targets.
  3. [Abstract, Section 5, and Table 2] The abstract and conclusion state that the proposed method 'outperformed all but one of 20 competing models' without specifying that this ranking is under the log-weighted interval score (LWIS). Table 2 shows that ASGD NORM2 has the best mean WIS but is second to UGA flucast-INFLAenza on mean LWIS and median LWIS, so the claim is sensitive to the scoring rule. The authors should state the criterion in the abstract and conclusion, or limit the claim to the LWIS metric, to avoid the impression that the proposed model dominates under all reported scores.
minor comments (5)
  1. [Section 3.8] The description of the posterior predictive sampling says that negative values were 'set to 0,' but it does not describe how the corresponding quantiles were recomputed after truncation; a brief explanation of the quantile construction from the truncated samples would improve reproducibility.
  2. [Equation (9)] The weighted interval score formula uses the index k in the summation and the weight w_k, while the surrounding text defines the weights as w_b; this notational inconsistency should be fixed.
  3. [Figure 9 caption and Section 5 text] The caption says 'the 21 models being compared' while the text says 'all 22 models being compared'; the count should be reconciled, especially because Table 2 includes both ASGD NORM2 and SIRD NORM2 in addition to the 20 external FluSight models.
  4. [Throughout] There are numerous typos and misspellings, including 'assymetric,' 'intveral,' 'hierarhical,' 'remeiniscent,' 'indicateds,' 'referrred,' and 'NOMR2' in Section 5; a careful copyedit is needed.
  5. [Section 4] The simulation study fixes the hospitalization parameters at posterior means from the 2022 season and chooses weeks 14, 20, 26, 32, and 38 for forecasting, but it does not state a random seed or provide code for replicating the 500 Monte Carlo replicates; including these details would strengthen reproducibility.

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity: the central comparison is against external FluSight submissions and the derivation is self-contained; the empirical-Bayes prior timing is an unresolved leakage risk, not a demonstrated circular step.

full rationale

The claimed derivation is not circular. The main real-data claim—ASGD NORM2 'outperformed all but one' of 20 FluSight models—is evaluated against externally submitted FluSight forecasts held on a public hub (Section 5; Table 2), so the benchmark is not generated by the paper's model. The two-component construction (ILI model (1), hospitalization model (6), Bayesian-cut combination (7)-(8)) is a modular pipeline; hospitalization forecasts are posterior predictive draws from fitted parameters, not identities with the inputs. The simulation study simulates log-hospitalizations from parameters fitted to 2022 data and then scores the models, which is a model-consistency check rather than a circular prediction. Prior selection follows Osthus et al. and Ulloa with explicit changes; no uniqueness theorem or author-imported constraint forces the chosen model. The only concern that could threaten the out-of-sample interpretation is the empirical-Bayes prior in Section 3.6 (θ centered on MLEs of λ_s 'across all seasons') combined with the statement in Section 3.8 that models were 'fit using US national data from 2010 to 2023'; if the 2023 MLE used the full season, forecasts for 2023 would have future information. But the text does not establish that the full-season 2023 MLE entered the prior used at each forecast week, and the forecasts are not algebraically forced by any fitted parameter, so this is an unresolved data-leakage/correctness risk, not demonstrated circularity. The paper's own caveat that performance may vary by season (Section 6) is a limitation, not a circular step.

Assumptions & free parameters 3 free parameters · 7 assumptions · 0 invented entities

The framework's forecasts rest on standard statistical models plus several hand-chosen constraints and an empirical Bayes prior whose timing relative to the forecast period is unstated. The most consequential fitted inputs are the empirical Bayes hyperparameters for the ASG offset, which affect every forecast. The other axioms are domain assumptions common in flu forecasting, listed for completeness.

free parameters (3)
  • Empirical Bayes prior mean for ASG offset lambda_s = Mean of MLEs across seasons (exact value not reported)
    Centers the hierarchical prior for lambda_s in the ASGD model. If the MLEs include the target season, this parameter is fitted to the outcome being forecast; the paper does not specify the timing.
  • Empirical Bayes prior variance (tightness) for lambda_s = Not stated; set to be tight around the mean
    Chosen to improve posterior mixing and forecasts, i.e., tuned using the evaluation data.
  • Scaling factor P = Total population / 50,000
    Fixed transformation to scale ILI before entering the hospitalization model; not fitted but a modeling choice affecting all forecasts.
assumptions (7)
  • domain assumption Beta distribution with logit link adequately models weekly ILI proportions
    Model (1) assumes ILI_s,w ~ Beta with mean pi_s,w; a standard assumption but untested against other error distributions.
  • domain assumption The SIR or ASG function captures the main trajectory of ILI, and reverse random-walk discrepancy terms capture remaining systematic patterns
    Centers the entire ILI modeling approach; evidence is empirical via MLE fits and forecast comparisons.
  • ad hoc to paper ILI data from seasons 2010-2022 (excluding 2020) are informative for forecasting future seasons, and the 2020 season is an anomaly that can be discarded
    The paper excludes 2020 due to COVID-19 effects; this exclusion is a modeling decision made after observing the data.
  • domain assumption Hospitalizations are a linear/quadratic function of ILI with an AR(1) term, and the error is normally distributed
    Model (6) and Section 5; validated only for log-transformed hospitalizations in the simulation study.
  • domain assumption Bayesian cut approximation: fitting the ILI and hospitalization modules separately and plugging in ILI forecast draws yields valid predictive distributions
    Section 3.7; the authors justify by convergence, time, and forecast performance, but this is an approximation without formal guarantees.
  • ad hoc to paper The reverse random-walk discrepancy with sum-to-zero constraint is identifiable and generalizes to new seasons
    Section 3.4; requires constraints and informative priors to estimate; generalization to future seasons is an assumption.
  • ad hoc to paper Setting the initial susceptible fraction S0 = 0.9 in the SIR model
    Section 3.6; fixed for identifiability following Osthus et al.

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Pith. "Pith review of Forecasting Influenza Hospitalizations Using a Bayesian Hierarchical Nonlinear Model with Discrepancy." pith.science (2026). https://pith.science/paper/GH6GMWTG

@misc{pith2026241214339,
  author       = {Pith},
  title        = {Pith review of: Forecasting Influenza Hospitalizations Using a Bayesian Hierarchical Nonlinear Model with Discrepancy},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/GH6GMWTG}},
  note         = {Machine review of arXiv:2412.14339}
}
read the original abstract

The annual influenza outbreak leads to significant public health and economic burdens making it desirable to have prompt and accurate probabilistic forecasts of the disease spread. The United States Centers for Disease Control and Prevention (CDC) hosts annually a national flu forecasting competition which has led to the development of a variety of flu forecast modeling methods. Beginning in 2013, the target to be forecast was weekly percentage of patients with an influenza-like illness (ILI), but in 2021 the target was changed to weekly hospitalizations. Reliable hospitalization data has only been available since 2021, but ILI data has been available since 2010 and has been successfully forecast for several seasons. In this manuscript, we introduce a two component modeling framework for forecasting hospitalizations utilizing both hospitalization and ILI data. The first component is for modeling ILI data using a nonlinear Bayesian model. The second component is for modeling hospitalizations as a function of ILI. For hospitalization forecasts, ILI is first forecast then hospitalizations are forecast with ILI forecasts used as a predictor. In a simulation study, the hospitalization forecast model is assessed and two previously successful ILI forecast models are compared. Also assessed is the usefulness of including a systematic model discrepancy term in the ILI model. Forecasts of state and national hospitalizations for the 2023-24 flu season are made, and different modeling decisions are compared. We found that including a discrepancy component in the ILI model tends to improve forecasts during certain weeks of the year. We also found that other modeling decisions such as the exact nonlinear function to be used in the ILI model or the error distribution for hospitalization models may or may not be better than other decisions, depending on the season, location, or week of the forecast.

Figures

Figures reproduced from arXiv: 2412.14339 by the authors.

Figure 1
Figure 1. Percentage of outpatient visits with an influenza-like illness (ILI) in the US for seasons 2010 to 2023 (top) [PITH_FULL_IMAGE:figures/full_fig_p004_1.png] view at source ↗
Figure 2
Figure 2. Susceptible-infectious-recovered (SIR) model separated by compartments. The three compartments are the [PITH_FULL_IMAGE:figures/full_fig_p006_2.png] view at source ↗
Figure 3
Figure 3. Example plot of asymmetric Gaussian (ASG) function showing the shape of the function in relation to the [PITH_FULL_IMAGE:figures/full_fig_p007_3.png] view at source ↗
Figures from the paper (7 more)
Figure 4
Figure 4. Figure 4: Observed US national influenza-like illness (ILI) percentage for seasons 2010 to 2022 excluding 2020 (grey) [PITH_FULL_IMAGE:figures/full_fig_p007_4.png]
Figure 5
Figure 5. Figure 5: Difference between observed US national influenza-like illness (ILI) and MLE fits for an asymmetric Gaussian [PITH_FULL_IMAGE:figures/full_fig_p008_5.png]
Figure 6
Figure 6. Figure 6: Scatterplots of national hospitalizations (left) or log hospitalizations (right) lag differences by ILI % where [PITH_FULL_IMAGE:figures/full_fig_p009_6.png]
Figure 7
Figure 7. Figure 7: Results of forecasts for simulated hospitalizations for ASGD, ASG, SIRD, SIR, BASE, and ARIMA models. [PITH_FULL_IMAGE:figures/full_fig_p013_7.png]
Figure 8
Figure 8. Figure 8: Forecasts 1-4 weeks ahead for US hospitalizations during the 2023 season for weeks 14, 20, 26, and 32. [PITH_FULL_IMAGE:figures/full_fig_p014_8.png]
Figure 9
Figure 9. Figure 9: a) Log-weighted interval score (LWIS) averaged over location and horizon for each week during the season [PITH_FULL_IMAGE:figures/full_fig_p015_9.png]
Figure 10
Figure 10. Figure 10: Ratio of average log-weighted interval score (LWIS) for ASGD [PITH_FULL_IMAGE:figures/full_fig_p016_10.png]

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Forward citations

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Reference graph

Works this paper leans on

28 extracted references · 25 canonical work pages · cited by 1 Pith paper

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    FORECASTING INFLUENZA HOSPITALIZATIONS USING A BAYESIAN HIERARCHICAL NONLINEAR MODEL WITH DISCREPANCY Spencer Wadsworth University of Connecticut Storrs, Connecticut iac25002@uconn.edu Jarad Niemi Iowa State University Ames, Iowa niemi@iastate.edu ABSTRACT The annual influenza outbreak leads to significant public health and economic burdens making it desi...

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    The function is defined in (3)

    The ASG function is denoted as 𝐴𝑆𝐺𝜃(𝑤) where𝜃=(𝜆,𝜈,𝜇,𝜎 2 1,𝜎 2 2),𝜈 >0,𝜆 >0, 𝜇∈(−∞ ,∞),𝜎1,𝜎 2 > 0 and𝑤∈( 1,...,𝑊 ) is week. The function is defined in (3). 𝐴𝑆𝐺𝜃(𝑤)= 𝜆+(𝜈−𝜆)exp[−(𝑤−𝜇)2/2𝜎2 1], 𝑤 < 𝜇 𝜆+(𝜈−𝜆)exp[−(𝑤−𝜇)2/2𝜎2 2], 𝑤 ≥ 𝜇 (3) In this manuscript, we use a slightly reparameterized version of function (3) shown in (4), where𝜂=𝜈−𝜆 >0. This constraint...

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    2 Flu outbreak data In this section we introduce, define, and visually evaluate ILI and hospitalization data

    Finally, the manuscript is concluded in section 6 with general observations and some discussion. 2 Flu outbreak data In this section we introduce, define, and visually evaluate ILI and hospitalization data. ILI and hospitalization data have been the object of forecasting for FluSight with ILI being the target for the first seven seasons, 2013 to 2019, and...

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    Step 1: Sample g𝐼𝐿𝐼 ∗ 𝑠,𝑤 :(𝑤+4) Step 2: Sample 𝛼∗ 0𝑠,𝛼∗ 1𝑠,𝛼∗ 2𝑠,𝜙∗,𝜎∗ 𝜖𝑠,𝜔∗ 𝑠 from respective marginal posterior distributions Step 3: Sample 𝐻∗ 𝑠,𝑤+𝑖 from𝐷(𝜔∗ 𝑠,𝜇∗ 𝑠,𝑤+𝑖,𝜎 2 𝜖𝑠), where 𝜇∗ 𝑠,𝑤+𝑖 =𝛼∗ 0𝑠+𝛼∗ 1𝑠(𝐼𝐿𝐼∗ 𝑠,𝑤+𝑖×𝑃)+ 𝛼∗ 2𝑠(𝐼𝐿𝐼∗ 𝑠,𝑤+𝑖×𝑃)2+𝜙∗𝐻∗ 𝑠,𝑤+𝑖−1 Step 4: Repeat step 3 for 𝑖∈{ 1, 2, 3, 4} to obtain𝐻∗ 𝑠,(𝑤+1):(𝑤+4) Step 5: Repeat steps 1-4 𝐾 tim...

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    Ensemble forecasts of coronavirus disease 2019 (COVID-19) in the US

    Evan L Ray, Nutcha Wattanachit, Jarad Niemi, Abdul Hannan Kanji, Katie House, Estee Y Cramer, Johannes Bracher, Andrew Zheng, Teresa K Yamana, Xinyue Xiong, et al. Ensemble forecasts of coronavirus disease 2019 (COVID-19) in the US. medRxiv, pages 2020–08,

  15. [2014]

    Notable from the plots in the top of figure 1 is the regular trajectory of the ILI

    This convention is used for the remainder of this manuscript. Notable from the plots in the top of figure 1 is the regular trajectory of the ILI. With the exception of season 2020, the ILI begins low at week 1 and increases as the fall and winter progress until the ILI reaches...

  16. [2015]

    and Nott et al. [2023]. Cutting a model into two component models or “modules“ may be justfied for several reasons including to reduce time to fit the model, avoiding mixing issues of posterior sampling distributions, improving predictive performance or to prevent model misspe...

  17. [2021]

    Initially the target data for forecasts was influenza-like illness (ILI) data. ILI is the proportion of patients who meet a healthcare provider and who display flu like symptoms, and ILI data has been available at the state and national level since the 2010 flu season [CDC, 20...

  18. [2022]

    Anne Ewing, Elizabeth C Lee, C´ecile Viboud, and Shweta Bansal

    URL https://doi.org/10.1038/s41597-022-01517-w . Anne Ewing, Elizabeth C Lee, C´ecile Viboud, and Shweta Bansal. Contact, travel, and transmission: the impact of winter holidays on influenza dynamics in the United States. The Journal of Infectious Diseases, 215(5):732–739,

  19. [2023]

    To better align with the flu behavior, week 1 is set as the first week of August and week 52 or 53 is the last week in July of the following year

    For most seasons there are 52 weeks listed, but for the 2010, 2015, and 2021 seasons there are 53 weeks because those seasons had 53 Sundays. To better align with the flu behavior, week 1 is set as the first week of August and week 52 or 53 is the last week in July of the foll...

  20. [2024]

    R package version 0.7.1, https://discourse.mc-stan.org. Roberto C Garza, Ricardo Basurto-D´avila, Ismael R Ortega-Sanchez, Luis Oreste Carlino, Martin I Meltzer, Rachel Albalak, Karina Balbuena, Pablo Orellano, Marc-Alain Widdowson, and Francisco Averhoff. Effect of winter sch...

Pith tools

Reviewed August 11, 2026 · model on record in the stance chip above.