Robustness of time series analysis

In summary, the conversation discusses ways to improve the robustness of a time series model, specifically through expanding data and increasing the number of lags. However, this may have the opposite effect if done incorrectly. Other methods, such as examining outliers and using GMM to correct for autocorrelation, are also suggested. Additionally, decreasing the time step of the time series may be beneficial, but it is important to not solely rely on the Nyquist sampling frequency.
  • #1
monsmatglad
76
0
I have a time series model constructed by using ordinary least square (linear).
I am supposed to provide some general comments on how one would improve the robustness of the analysis of a time series model (in general).
Are there any general advice apart from expanding data, making it more frequent and increasing the number of lags?

Mons
 
Physics news on Phys.org
  • #2
None of those makes a T.S. regression more robust other than more data. Robust means that the model can work if the assumptions about normally distributed variables, homoskedasticity, no autocorrelation etc are relaxed. Examining outliers and the impact they have is a good starting place. Testing the model out of sample using GMM to correct for autocorrelation are other methods.
 
  • Like
Likes FactChecker
  • #3
monsmatglad said:
I
Are there any general advice apart from expanding data, making it more frequent and increasing the number of lags?
Increasing the number of lags will have the opposite effect if you are talking about including terms with less statistical significance.

It's not clear to me what "making it more frequent" means. If that means decreasing the time step of the time series, then that may help. Especially if the current time step is too large to capture important high frequencies. Do not make the mistake of assuming that the Nyquist sampling frequency is adequate. It is the minimal sample frequency that will give perfect accuracy if you have an infinite time-length sample. Any finite time-length sample gives less than perfect accuracy.
 

Related to Robustness of time series analysis

1. What is robustness in time series analysis?

Robustness in time series analysis refers to the ability of a statistical model or method to produce reliable and accurate results in the presence of outliers, errors, or other disturbances in the data. It is an important aspect to consider when conducting time series analysis as it ensures the validity of the results.

2. Why is robustness important in time series analysis?

Robustness is important in time series analysis because real-world data often contains unpredictable fluctuations, errors, or outliers that can significantly impact the results of the analysis. A robust model or method can handle these disturbances and still produce accurate and reliable results, making it more suitable for practical use.

3. How is robustness measured in time series analysis?

There are several measures used to evaluate the robustness of a time series analysis, such as the median absolute deviation, the trimmed mean, and the median absolute percentage error. These measures compare the results of the analysis with and without the presence of outliers to determine the impact on the results.

4. What are some common techniques for improving the robustness of time series analysis?

Some common techniques for improving the robustness of time series analysis include using robust statistical models, such as the median or trimmed mean, instead of the mean, which is sensitive to outliers. Other techniques include data transformation, such as taking the logarithm of the data, and using robust estimators, such as the Huber estimator.

5. Can a time series analysis be considered robust if it is only robust to a specific type of disturbance?

No, a time series analysis can only be considered robust if it can handle a wide range of disturbances or outliers in the data. If a method or model is only robust to a specific type of disturbance, it may not be suitable for real-world data, which can contain various types of disturbances. It is important to test the robustness of a time series analysis to multiple types of disturbances to ensure its validity.

Similar threads

  • Set Theory, Logic, Probability, Statistics
Replies
8
Views
562
  • Set Theory, Logic, Probability, Statistics
Replies
6
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
7
Views
579
  • Set Theory, Logic, Probability, Statistics
Replies
10
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
4
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
4
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
2
Views
2K
  • Set Theory, Logic, Probability, Statistics
Replies
8
Views
2K
  • Set Theory, Logic, Probability, Statistics
Replies
5
Views
7K
  • Set Theory, Logic, Probability, Statistics
Replies
4
Views
4K
Back
Top