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Table 1 Notation and Symbols

From: A framework for evaluating epidemic forecasts

Symbol

Definition

y(t)

number of new cases of disease in the t th week observed in surveillance data

x(t)

number of new cases of disease in the t th week predicted by forecasting methods

x start

number of new cases of disease predicted at the start of epidemic season

x peak

predicted value of the maximum number of new cases of the disease

e t

e t =y t x t : the prediction error

T

duration of the epidemic season

\( \bar {y} \)

\(\bar {y}=\frac {1}{T} \sum _{t=1}^{T} (y_{t}) \) : the mean for y values over T weeks

σ 2

\( \sigma ^{2}=\frac {1}{T-1} \sum _{t=1}^{T} (y_{t}-\bar {y})^{2} \) : The variance of y values over T weeks

n tot

Total number of infected persons during specified period

n ps

The population size at the start of specified period

n tot (a g e)

Total number of infected persons with specific age during the specified period

n ps (a g e)

The population size with specific age at the start of specified period

n c

or n contacts is the number of contacts of primary infected persons

n sg

or n s e c o n dg e n e r a t i o n is the new number of infected persons among the contacts of primary infected individuals during a specified period

G M{E r r o r}

\( GM(e)= \left (\prod _{i=1}^{n}(e_{i})\right)^{(1/n)} \) : Geometric Mean of a set of Errors

M{E r r o r}

Arithmetic Mean of a set of Errors

M d{E r r o r}

Median value of a set of Errors

R M S{E r r o r}

Root Mean Square of a set of Errors