Higher-moment statistics are used to detect possible instrument or recording problems and physical but unusual behavior. Any linear trend in the series is removed prior to computing the higher moment statistics to remove any potential contribution of the trend to the skewness and kurtosis. The linear detrending of the data is applied only for the purpose of calculating the higher moment statistics and is not used for the rest of the tests. The skewness and kurtosis of the fields are computed for the entire record. The record is hard flagged when the skewness is outside the range (−2, 2) or the kurtosis is outside the range (1, 8). Skewness and kurtosis values outside this range represent excursions from the mean that are beyond normal physical expectations. These limits are empirically based on the datasets considered here. The record is soft flagged when the skewness is outside the range (−1, 1) or the kurtosis is outside (2, 5).