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waico / SKAB

SKAB - Skoltech Anomaly Benchmark. Time-series data for evaluating Anomaly Detection algorithms.
GNU General Public License v3.0
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Changepoint issue #43

Open waystogetthere opened 2 years ago

waystogetthere commented 2 years ago

Hi, I have some questions about the column: 'changepoint'. According to my last post(thanks Kaster! you're really helpful!) : https://www.kaggle.com/datasets/yuriykatser/skoltech-anomaly-benchmark-skab/discussion/325533, the changepoint should indicate the status changing between 'normal' and 'anomaly': i.e. 'normal' to 'anomaly' or 'anomaly' to 'normal'.

However, when I checked the data, I found something unexpected.

I merged all .csv file under data/valve1/ and sort them by the column: datetime. There are 63 records with changepoint = 1, but only 32 indicate a status switching.

waystogetthere commented 2 years ago
valve1-wholepicture

The image above shows 2 columns: changepoint and anomaly. While I can see that during collective anomalies there are some changepoints = 1

waystogetthere commented 2 years ago
valve1-detail

if we look in detail (from 10am to 11am, 09 March), it is clearer.