If the values in V d are skewed towards the high side (negative skew), it means that the candidate entity is very likely to be a true entity, and we should take the median as it is also high (higher than the mean).
if the skew is towards the low side (positive skew), it means that the candidate entity is unlikely to be a true entity and we should again use the median as it is low (lower than the mean) under this condition.