3.1.2. Matching Process

As a result of ST-CORA, multiple storm events are identified in both observed and satellite data sets. However, it is necessary to determine the observed and estimated storm matches. We used the Intersection-over-Union measure (IoU) in order to evaluate the level of similarity between predicted and observed data. IoU is defined as the ratio between the size of the intersection and the union of both objects. This is represented by the following equation:

$$IoI = \frac{TP}{FP + TP + FN} \tag{4}$$

where, *TP* represents true positives and *FP* and *FN* are false positives and negatives, respectively. The selection of the intersection rate value determines the level of matching between objects. If the values are too low, multiple objects will be indexed with the same object. On the other hand, high values indicate that the object does not have any match. We found the *IoU* value to be 30 percent in the selected study area, which is a good balance for matching the observed and satellite storm events.
