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Accuracy of US CDC COVID-19 forecasting models.
Aviral Chharia1,2,3, Govind Jeevan1,2, Rajat Aayush Jha1,2
1Global Health Research Collective, Academics for the Future of Science, Cambridge, MA, United States.
Many COVID-19 forecasting models fail to outperform simple baselines. Pandemic modeling accuracy has not improved over time, raising concerns about their use in policy decisions.
Area of Science:
- Epidemiology
- Biostatistics
- Public Health Policy
Background:
- Accurate pandemic forecasting is crucial for resource allocation and policy.
- Numerous COVID-19 case prediction models exist, but their performance over time and by type is not well understood.
Purpose of the Study:
- To systematically analyze the accuracy of US Centers for Disease Control and Prevention (CDC) COVID-19 forecasting models.
- To compare model performance against government data, baseline models, and each other.
Main Methods:
- Categorization of US CDC COVID-19 forecasting models.
- Calculation of mean absolute percent error (MAPE) wave-wise and overall.
- Comparison with static and linear trend baseline models.
Main Results:
- Two-thirds of models did not outperform a static case baseline.
- One-third of models did not outperform a linear trend forecast.
- No single modeling approach consistently outperformed others; errors increased over time.
Conclusions:
- Many pandemic forecasting models lack predictive accuracy.
- Concerns exist regarding the reliability of models hosted on official public health platforms.
- A universal evaluation method is needed to drive the development of improved pandemic forecasting models.
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However, the point estimate is most likely not the exact value of the population parameter, but close to it. After calculating point estimates, we construct interval estimates, called confidence intervals or prediction intervals. This prediction interval comprises a range of values unlike the point estimate and is a better predictor of the observed sample value, y.
Residuals and Least-Squares Property
If the observed data point lies above the line, the residual is positive, and the line underestimates the actual data value for y. If the observed data point lies below the line, the residual is negative, and the line overestimates the actual data value for y.
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