Search found 184 matches: singular covariance
Searched query: singular covariance
- Tue Aug 12, 2025 12:20 pm
- Forum: General Information and Tips and Tricks
- Topic: Mathematical representation of a particular state space model
- Replies: 1
- Views: 19213
Re: Mathematical representation of a particular state space model
... That said, your interpretation of the H matrix is correct, H will be singular = 192*exp(c(1)) times a 2 x 2 matrix of 1s. As to the state error covariance, I am not sure why you say that it is 2 x 2. Perhaps you left off an equation, but ...
- Wed Aug 06, 2025 6:27 pm
- Forum: General Information and Tips and Tricks
- Topic: Mathematical representation of a particular state space model
- Replies: 1
- Views: 19213
Mathematical representation of a particular state space model
... II on State Space Models, my interpretation is as follows: Signal Error Covariance (2x2, H matrix): Since the same named error E1 is used in both signal equations, the resulting H matrix is singular, with all of its elements being equal to 192*EXP(C(1)). Is this correct? ...
- Tue Apr 16, 2024 2:50 pm
- Forum: Estimation
- Topic: Maximum likelihhod estimator sspace showing the result of Probability, z statistic, and standard error as NA
- Replies: 1
- Views: 29343
- Tue Apr 16, 2024 2:31 pm
- Forum: Estimation
- Topic: Maximum likelihhod estimator sspace showing the result of Probability, z statistic, and standard error as NA
- Replies: 1
- Views: 29343
Maximum likelihhod estimator sspace showing the result of Probability, z statistic, and standard error as NA
... observations: 46 Convergence achieved after 29 iterations Coefficient covariance computed using outer product of gradients WARNING: Singular covariance - coefficients are not unique Coefficient Std. Error z-Statistic Prob. ...
- Mon Feb 06, 2023 2:52 am
- Forum: Estimation
- Topic: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
- Replies: 6
- Views: 14275
Re: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
Thanks Startz, that's really helpful! I'll have a go away and look into what I can replace it with, if anything!
- Fri Feb 03, 2023 11:45 am
- Forum: Estimation
- Topic: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
- Replies: 6
- Views: 14275
Re: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
The model looks a bit like the following: DLOG(Y) = C(1) + C(2)*(LOG(Yt-1) + C(3)*LOG(Xt-1) + (1-C(3))*LOG(Zt-1)) + C(4)*DLOG(Xt-1) + C(5)*DLOG(Zt-1) + (1-C(4)-C(5))*DLOG(Ut) Where I'd want constraints such as: -1 < C(2) and C(3) < 0 C(4) and C(5) >0 I @LOGIT some of the coefficients to get round t...
- Fri Feb 03, 2023 10:07 am
- Forum: Estimation
- Topic: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
- Replies: 6
- Views: 14275
Re: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
In the generic model you posted, the only thing that's nonlinear is c(3). If your real model is different from that then it's hard to say much without seeing the real model. The model looks a bit like the following: DLOG(Y) = C(1) + C(2)*(LOG(Yt-1) + C(3)*LOG(Xt-1) + (1-C(3))*LOG(Zt-1)) + C(4)*DLOG...
- Fri Feb 03, 2023 7:07 am
- Forum: Estimation
- Topic: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
- Replies: 6
- Views: 14275
Re: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
In the generic model you posted, the only thing that's nonlinear is c(3). If your real model is different from that then it's hard to say much without seeing the real model.
- Fri Feb 03, 2023 3:15 am
- Forum: Estimation
- Topic: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
- Replies: 6
- Views: 14275
Re: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
What do you get for point estimates? I'll get values of something like -0.5 for a coefficient that should be 0.5. Also all the variables are logged! It's also built into an error correction framework, so sometimes the long-run variable will have the right sign while the short-run differenced one wi...
- Thu Feb 02, 2023 11:36 am
- Forum: Estimation
- Topic: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
- Replies: 6
- Views: 14275
Re: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
What do you get for point estimates?
- Thu Feb 02, 2023 9:38 am
- Forum: Estimation
- Topic: Overconstrained model - Constraints too restrictive leading to Singular Covariance error
- Replies: 6
- Views: 14275
Overconstrained model - Constraints too restrictive leading to Singular Covariance error
... starting values for the parameters I will get the error: "WARNING: Singular covariance - coefficients are not unique" with NA's in place of the std. errors, t-stats, ...
- Wed Nov 30, 2022 3:54 pm
- Forum: Programming
- Topic: singular covariance in Kalman filtering
- Replies: 1
- Views: 3696
Re: singular covariance in Kalman filtering
It is the covariance of the coefficients. It is a little difficult to diagnose without looking at ... I think you are right about overidentification. I will note that in the second (non-singular) parameterization, you are only estimating a single share coefficient instead of ...
- Wed Nov 30, 2022 3:04 pm
- Forum: Programming
- Topic: singular covariance in Kalman filtering
- Replies: 1
- Views: 3696
singular covariance in Kalman filtering
Hi, I have a concern about a "singular covariance" message which came with the output of a Kalman filter estimation. I am wondering which ...
- Fri Sep 02, 2022 4:42 am
- Forum: Programming
- Topic: WARNING: Singular covariance - coefficients are not unique
- Replies: 0
- Views: 14050
WARNING: Singular covariance - coefficients are not unique
... State Space equations, but I encounter this message "WARNING: Singular covariance - coefficients are not unique" on state space output. I have been trying to ...
- Tue May 17, 2022 3:30 am
- Forum: Estimation
- Topic: logistic using binary variable
- Replies: 3
- Views: 5422
Re: logistic using binary variable
... 1 1004 Included observations: 919 Failure to improve likelihood (singular hessian) after 6 iterations Coefficient covariance computed using observed Hessian WARNING: Singular covariance - coefficients are ...
