Reconstructing Improper Values with Reference Data

Causal Step

This step uses the reference data to reconstruct improper values. An improper value $Y_i$ at time step $i$ is estimated using the following formula:

$${\hat{Y}_i = \frac{Y_{i-1}}{Y^r_{i-1}} Y^r_i}\quad\text{,}$$

where $\hat{Y}_i$ is the reconstructed value at time step $i$ and $Y^r_i$ is the reference data value at time step $i$.

Input Parameters

1. Input data including improper values
2. Definition of improper values (‘nan’, ‘inf’, or ‘null’, etc.)

Output Parameters

1. Output data excluding improper values

Workflow

References

• T. Bellemans, B. De Schutter, and B. De Moor, Data acquisition, interfacing and pre-processing of highway traffic data, In Proceedings of Telematics Automotive 2000, Birmingham, UK, vol. 1, pp. 4/1-4/7, Apr. 2000.