Rick Vierra
04/30/2025, 6:22 PMyang.jia@xiaoandigital.com
Hi Rick,
thanks for the PPT. I put our questions down here
1. what's the relationship between single variable and multivariate anomaly detection? From the example in online documation, It looks to me multivariate anomaly detection is based on simple summation of deviation of all single variables and their forcasts, greater than some threshold values and decide the false points. Otherwise, what's the mechanism? is there correlation factors in consideration? https://docs.nixtla.io/docs/capabilities-online-anomaly-detection-univariate_vs_multivariate_anomaly_detection
2. how to detect abormal temperature on a time patterned temperature curve (sinusodal shape due to day and night temperature difference) I attached an example for our sensor's curve in chemical plant, it didn't return the satisfactory results regardliess confidence level tuning. My teammate Yusheng adjusted stepsize and horizon, and didn't get better result either.
3. https://github.com/Nixtla/nixtla/issues/641 this is Yusheng's specific code questions
4. can you please provide license options? is there any pay-as-you-go billing option?
best regards
Yang jia
Rick Vierra
04/30/2025, 6:32 PMHan Wang
04/30/2025, 7:12 PMHan Wang
04/30/2025, 7:12 PMRick Vierra
04/30/2025, 7:25 PMHan Wang
04/30/2025, 7:39 PMHan Wang
04/30/2025, 7:39 PMMarco
05/05/2025, 12:16 PMRick Vierra
05/05/2025, 4:39 PMHan Wang
05/05/2025, 5:50 PMRick Vierra
05/06/2025, 6:10 PMRick Vierra
05/07/2025, 2:13 PMMarco
05/13/2025, 2:13 PMF1-score: 0.71
Precision: 0.99
Recall: 0.55
Basically, it means that when TimeGPT flags an anomaly, it's right 99% of the time, and it successfully identifies 55% of the anomalies.
I calculated this based on whether the current is 0 or not. If 0, normal value, if greater than 0, I label it as an anomaly (ground truth). This is maybe wrong, but that's what I understand from their process.
These results are obtained when sampling the data at every minute. So, there is a bit of a lag when detecting anomalies. but it's in the order of seconds.
Here's the TimeGPT call with the anomaly detection method:
current_anomalies_1T = client.detect_anomalies(df=clean_df, freq="1min", model="timegpt-1-long-horizon")
and plot:Marco
05/13/2025, 2:45 PMMarco
05/13/2025, 3:06 PMRick Vierra
05/13/2025, 3:58 PM