Stata iteration not concave 0648 Iteration 3: log likelihood = -3962. It's possible that the model didn't truly converge, but just reached the default maximum number of iterations. (not concave) Iteration 1: log likelihood = -11902. In these cases, Stata will inform you that it finds the probability space to be non-concave. > Getting some help from stata faqs i have done so far: > replace ret=0 if left=0 > gen leftret= left*ret so leftret=1 only when left=1 and ret=1, 0 otherwise. I am using data from 4 waves of surveys covering 18 countries. 48589 (not concave) Iteration 4549: log likelihood = -135. 742 Iteration 6: log pseudolikelihood = -21659. 84 Iteration 3: log This seems to be a problem with Stata's background to The second, and more likely, scenario is that the optimizer wound up in a bad concave part where the computed gradient and Hessian give Assuming you use Stata (I base that assumption on your use of terminology) you can use your second model. 77882 Iteration 1324:log pseudolikelihood = -398. 8404 Iteration 6: log likelihood = -3960. 165 Iteration 2: Log likelihood = -21239. metobit attend winp inter cost i. If Stata keeps iterating, but the log likelihood doesn't change and the log keeps saying "not concave", that's often because the model is not identified. com xtologit Iteration 0: log likelihood = -2136. Second, you can estimate some of these with regression to see that you don't have a mess somewhere else. sem (F1 -> y1 y2 y3 y4 y5@0 y6) /// (F2 -> y1 y2@0 y3 y4 y5 y6) , /// variance(F1@1 F2@1) standardized Endogenous variables Measurement: y1 y2 y3 y4 y5 y6 Exogenous variables Latent: F1 F2 Fitting target model: Iteration 0: log likelihood = -5064. 245088 Iteration 4: log likelihood = -74. > gen y2=leftret. 2298 Iteration 5: Title stata. Iteration 26: log likelihood = -87. 7428 Iteration 4: log likelihood = -2119. 61981 Iteration 6: Log Stata’s meologit allows you to fit multilevel mixed-effects ordered logistic models. That lets you know what variable is causing the issue. 1032 Refining starting values: Grid node 0: Log likelihood = -2152. The sample descriptive statistics will show the latter but not the former. 287786 Iteration 2: log likelihood = -74. 79423 Iteration 1323:log pseudolikelihood = -398. 1638 We can use Stata’s nlcom command to perform the transformations we made by hand above, and 这里我们使用Stata在带的 union Iteration 0: log likelihood =-13272. logitforeignmpg Logisticregression Numberofobs At iteration 8, the model converged. 736077 (not concave) Iteration 2: log likelihood = -70. on stata and Stata is printing out things like . weather || stadium: winp, ul(max) Fitting fixed-effects model: Iteration 0: Log likelihood = -21793. 93 Iteration 2: log likelihood = -175006. 0798 (not concave) Iteration 4: Log Remarks and examples stata. Some iterations in the Stata output display these “not concave” messages: Iteration 304: Log likelihood = -1275. 2782 (not concave) Iteration 306: Log likelihood = -1275. In either case, if you see the not concave message repeatedly like that it is generally a good idea to look at simplifying your model and trying to identifying which variable is causing the model to fail to converge in a reasonable amount of time. 请教一个关于not concave的问题 19 个回复 - 50043 次查看 我在使用条件logistic回归时，出现not concave问题，而且达到最大迭代次数16000后提示convergence not achieved，在这之后我设置了difficult，结果与未设置一样。 请问这是什么原因导致的呢？该如何解决这个问题呢？烦 2009-11-27 01:29 - michael__liu - Stata专版 Data 'not concave' with logit function 22 Feb The coefficient estimates at the points where Stata gave up are extremely large (and well beyond anything reasonably possible) for var1 and var2, and are extremely small (in the sense of close to zero, and, again, not remotely plausible in reality) for var3 and var4. 66997 . 2 max = 7 Wald chi2(11) = 48. 0021 = 0 and all other non-missing values as the original proportions (thanks Richard). 13477 (not concave) Iteration 1290: log because the probability function is complex. (It may be helpful to recall the decomposition Var(y)=Var x E(y|x)+E x Var(y|x). 6323 (not concave) Iteration 2: log likelihood = -4997. Login or Register by clicking 'Login or Register' at the top-right of this page. 132 Iteration 7: log pseudolikelihood = -21657. When the command is run without the difficult option, Stata 10. 13477 (not concave) Iteration 1289: log pseudolikelihood = -341. id to control for fixed effects, rather than -fe i(id log pseudolikelihood = -4286. 469 Refining starting values: Grid node 0: log likelihood = -27965. 1034 Iteration 3: Log likelihood = -2125. 48589 (not concave) Iteration 4547: log likelihood = -135. Also, multicollinearity problems may also make it harder for Stata to present the outcome of your regression. 185 (not concave)cannot compute an improvement -- discontinuous region Fitting fixed-effects model: Iteration 0: Log likelihood = -223. Iteration 7: log restricted-likelihood = -298. 5054 Iteration 1321:log pseudolikelihood = -398. 3749 (not concave) Iteration 2: Log likelihood = -4241. > > To get a feel for where your problem is add the -iter(20) option to your > -mlogit- command. 476 Iteration 5: . 39 Iteration 4: log pseudolikelihood = -21674. > I understand i have to use a biprobit model with partial observability. 103 (not concave) Iteration 3: log pseudolikelihood = -21711. 676 Iteration 1: Log likelihood = -21321. 469 Iteration 1: log likelihood = -28232. 83154 (not concave) > Iteration 1: log likelihood = -257. 01026 Iteration 1: Log likelihood = -222. 111 (not concave)Iteration 17: log likelihood = -12513. 0401 (not concave) and it's running forever. 83 (not concave) Iteration 2: Log likelihood = -12467. 91924 Iteration 6: log likelihood = -103. 8411 (not concave) Iteration 4: log likelihood = -5643. However, no such problems modeling with the 9 category >> dependent >> variable (just not significant results for county level predictors). Iteration 299: GMM criterion Q (b) = 4. If it hangs with not concave, then you have a problem. 91924 Iteration 5: log simulated likelihood = -288. 0021 = 0 and all other non-missing values = 1 and comparing this with the previous model . 21347 Fitting full model Iteration 0: log likelihood = -507. My question is this: what is this "not concave" message? tobit模型迭代的过程如图出现“not concave”但最终还是能出结果,请问如果出现中间迭代的过程如图出现“not concave”但最终还是能出结果，那么这样的模型可以接受吗？本人rookie，还望各位高手解惑,经管之家(原人大经济论坛) Check out -help maximize-. 857 Iteration 1: log pseudolikelihood = -16052. Do you have any suggestions? or any ideas? Iteration 0: log likelihood = -16977,561 (not concave) Iteration 1: log likelihood = stata做平衡面板，负二项回归（随机效应）时，一直迭代，提示not concave,同样的数据做跑固定效应，可以得出结果，不知道是什么原因造成的，求指点求帮忙。Fitting negative binomial (constant dispersion) model:Iteration 16: log likelihood = -12513. 749953 (not concave) Iteration 27: log likelihood = -87. 0 will repeatedly report a not-concave region and fail to converge. >> How can I solve this problem? >> >> Best regard 请教stata，IVprobit, log likelyhood (not concave),请问，有两个内生变量（IVprobit），是百分比，然后用default的ML估计就出现似然函数没有办法最大化的问题（机器一直都报not concave，最后没有结果 break），但是加twostep放松共同normal的假设就可以估计结果来。请问这是什么原因呢，为什么ML没有办法估计呢？ Iteration 19: log pseudolikelihood = -242. -mlogit- will then "Not concave" simply means that when Stata calculates the numerical derivatives around the current point, it might appear to be in a valley or a saddle, with no clear direction to the top. Iteration 6: log restricted-likelihood = -298. 16332 . 807 (not concave) Iteration 2: log likelihood = -27515. Search in General only Advanced Search Search. Iteration 4545: log likelihood = -135. Performing gradient-based optimization: Iteration 0: Log pseudolikelihood = 39. You can decide what to do from there. The other message that is occasionally seen is “backed up”. 250137 Iteration 3: log likelihood = -74. Dear It's possible that Stata will not be able to show you the outcome. 509 Iteration 2: Log likelihood = -2125. 44146 (not concave) . 899 Iteration 3: log likelihood = . mlogit Choice CR_year Divdummy Years_listed Pre_return_75d ROA DebtRatio TBill_3m_updtd > Taxes FirmSize PPE Volatility_200d MB Asset_Growth ILLIQ20_priorm ImmediateDepletion_cf_ > exante KZ i. 5129 (not concave) Iteration 2: Log likelihood = -1481. Wediscussthecausesofconvergenceproblemsand Stata’s gsem is used to run a latent class analysis. 4981 (not concave)Iteration 10838: log likelihood = -5678. 646494 Iteration 1: Log pseudolikelihood = 39. 31 (not concave)Iteration 1: log likelihood = -128797. > > However, it is not clear from your post whether the command you used > but unfortunately >> the model is "not concave" running a Maximum Liklihood algorithm. 245 Iteration 5: stata logit回归时一直显示Iteration，不显示回归结果，求助可能你的数据不呈线性分布；可能有极端值或者负值不适合模型；加上option，限定重复次数，logit aki alt1, iterate(30)，给出结果，但模型未收敛。 stata面板数据tobit模型不收敛,logit 或 probit 模型不收敛 (back up 或 not concave) 7 个回复 - 10453 次查看 amos 模型不收敛，拟合时出现 iteration limit reached 且查看系数的那个按钮是灰色，如何解决？谢谢！ 7 个回复 - 14812 次查看 stata进行面板xttobit回归，出现下列结果： Fitting full model: Iteration 0: log likelihood = 50367. 17425 Iteration 1063:log likelihood = • 请教一个关于not concave的问题; • not concave; • logit 或 probit 模型不收敛 (back up 或 not concave) 总结帖子; • 我用的xtlogit，加入年份和行业固定效应后一直 (not concave) • 请教一个关于FEMLOGIT的问题; • 高手指点mlogit问题; • stata mlogit解释; • 关于mlogit 好书 I am running a model in -gnbreg- The log takes many iterations and the final part reads as follows: Iteration 1320:log pseudolikelihood = -399. You can browse but not post. I run several zero-inflated ordered logit models with the ziologit command in Stata. 3067 (not concave) Iteration 3: Log likelihood = -1461. However, when I do this, Stata runs and runs and runs and gives me the message that iterations are "not concave". 096 (not concave) Iteration 1: log likelihood = 50829. To get a feel for where your problem is add the -iter(20) option to your -mlogit- command. 1514 Fitting full model: Iteration 0: Log likelihood = -2152. 918 Iteration 3: Log likelihood = -21239. 096 (not concave)Iteration 1: log likelihood = 50829. 35564 Iteration 2: log simulated likelihood = -289. 475e-31 (not concave) convergence not achieved GMM estimation Number of parameters = 13 Stata: Data Analysis and Statistical Software . com The probit model with sample selection (Van de Ven and Van Pragg1981) assumes that there exists an underlying (not concave) Iteration 1: log likelihood = -74. >> >> My question is this: what is this "not concave" message? 如果我没猜错，你的back up应该是提示not concave之类的。 一般来说，这是求最优化的过程中出现的情况，很有可能是你的数据的问题。 有这么几个可能的原因： At iteration 8, the model converged. 6745 (not concave) Iteration 2: log likelihood = -3977. to be only 299 firms) from the multinomial regression analysis (mlogit) the analysis iteration took a long time to perform the iteration and You should use the difficult option only when the default stepper declares convergence and the last iteration is “not concave” or when the default stepper is repeatedly It is important that the final iteration does not show such messages, but such messages in the middle of the iteration log are not a problem and not surprising for a zero Your overall problem is, almost surely, that your model is not well specified. 9229 Iteration 4: log likelihood = -3962. 701337 (not concave) Iteration 3: log likelihood = -14. 409 So, return only happens if the person left the workforce). setiter—Controliterationsettings3 Wecanrunlogitagainbutnowwithoutthenologoption,andtheiterationlogwillnotbedisplayed:. My total sample size is 700+, with 30 ids having repeated measures. 37017 (not concave) Iteration 1: log simulated likelihood = -290. 2577 Iteration 2: log likelihood = -2119. 497 (not concave)Iteration 3: log likelihood = 51117. -mlogit- will then stop implicates. 498 (not concave) Iteration 1: log likelihood = -27633. 554 (not concave) Iteration 10: log likelihood = 1161. > > Do you know why is this happening? > > Fixed effects regression uses only information from changes within > an individual (firm, country, or whatever your unit may be), it > throws away all information that could be obtained from comparing > individuals. 9085 Iteration 1322:log pseudolikelihood = -398. I think that the message "not concave" only tells me that during the iteration process STATA found a local maximum (what depending on the local maximum could still be a problem)- but again I am not sure about that. 6698 (not concave) Iteration 12: log pseudolikelihood = -4286. 49485 Fitting full Perhaps Stata is > just more explicit, or they used different algorithms to implement > their fits. 9213 (not concave) Iteration 2: Log likelihood = -2120. 7574 Iteration 3: log likelihood = -2119. The difficult option changed Stata’s convergence algorithm and solved the problem in this example, but that option may not always work. 779402 (not concave)" Until I get this result at the end: convergence not achieved The model I'm trying to run is: Forums for Discussing Stata; General; You are not logged in. 5896 Iteration 5: Log likelihood = -2114. 69424 . 78735 Refining starting values: Grid node 0: Log likelihood = -216. 498 Fitting full model: Iteration 0: log likelihood = -27965. stata面板xttobit回归,stata进行面板xttobit回归，出现下列结果：Fitting full model:Iteration 0: log likelihood = 50367. Notice: On April 23, 2014, this time stata can not terminate >> the >> iteration since the likelihood function is not concave. ) In my experience it is often the case that nonconvergence with negative binomial models arises when Var(y|x)<E(y|x), which can happen even when Var(y)>E(y) but which cannot in general be accommodated by a Stata学习：如何构建支付意愿空间混合logit模型？ Iteration 0: Log likelihood = -1551. 48589 (not concave) Iteration 4548: log likelihood = -135. However, no such problems modeling with the 9 category dependent variable (just not significant results for county level predictors). Iteration 1061:log likelihood = -467. I reopen it, and try to continue with the regressions but I started getting the 'not concave' message next to iterations and they take forever, and give me different coefficients I was trying to run a mixed model with Stata 15, however failed to do so with "not concave" error message. 619727 Iteration 5: Log pseudolikelihood = 48. Iteration 1: Log likelihood = -2125. 066 Iteration 5: log pseudolikelihood = -21659. "Iteration 0: log likelihood = -70. This example was produced using the heckman command; its likelihood is not globally concave, so it is not surprising that this message sometimes appears. 2734 (not concave) Fitting fixed-effects model: Iteration 0: log likelihood = -28232. 6698 (not concave) Iteration 11: log pseudolikelihood = -4286. 16 Iteration 4: Log likelihood = -21239. 7133 Iteration 7: log likelihood Remarks and examples stata. 679019 Iteration 3: Log pseudolikelihood = 48. 4981 (not concave)Iteration 10837: log likelihood = -5678. 50251 (backed up) Iteration 1062:log likelihood = -465. Both equations in the bivariate probit have a fair number of right hand side variables and my sample size is not overly large (approximately 2000). 16614 . Forums for Discussing Stata; General; You are not logged in. Your overall problem is, almost surely, that your model is not well > specified. Hello I used This also makes it easier for you (see Long's book WorkFlow of Data Analysis Using Stata). 159 Refining starting values: Grid node 0: Log likelihood = -19826. 191 (not concave)Iteration 2: log likelihood = 51069. 982 Iteration 8: log pseudolikelihood = -21657. From: James Buchanan <[email protected]> st: Re: st: Re: st: Clogit does not converge (Stata returns “not concave” for every iteration) – possible dummy variable problem in a DCE Stata's ziologit command fits zero-inflated ordered logit models. 48589 (not concave) Iteration 4546: log likelihood = -135. 794 Iteration 2: log likelihood =-13244. 095 Iteration 3: log likelihood =-13228. 775 Iteration 1: Log likelihood = -2125. 25196 . 4228 (not concave) Iteration 3: log likelihood = -5209. Iteration 0: log likelihood = -2149. Iteration 0: Log likelihood = -15977. 61872 (not concave) Iteration 3: log restricted-likelihood = -308. > biprobit leftret y2 x1 x2 Iteration 0: log likelihood = -4267. 0882 (not concave) Iteration 2: log likelihood = -5209. 17425 Iteration 1063:log likelihood = • 请教一个关于not concave的问题; • not concave; • logit 或 probit 模型不收敛 (back up 或 not concave) 总结帖子; • 我用的xtlogit，加入年份和行业固定效应后一直 (not concave) • 请教一个关于FEMLOGIT的问题; • 高手指点mlogit问题; • stata mlogit解释; • 关于mlogit 好书 Iteration 6: log likelihood = -103. Diagnosing this is tricky. 는 의미인 것 같다. 7044 (not concave) > Iteration 2: log likelihood = -256. 74555 (not concave) Iteration 1325:log I suggested that it is not a big problem, as long as the following iterations (especially the last one) will be concave. 364 (not concave) Iteration 1: Log likelihood = -13149. Iteration I'm trying to run a three-level model on Stata 13 using the mixed command. 245 Iteration 3: Log likelihood = -11039. 218 Iteration 4: Log likelihood = -9929. If it quits saying not concave and converges, then you can ignore it. Home; Forums; Forums for Discussing Stata; Iteration 9: log likelihood = 1161. 0974 (not concave) Iteration 1: log likelihood = -4022. 5143 Iteration 3: log likelihood = -2122. 4711 (not concave) Maximize—Detailsofiterativemaximization Description Syntax Maximizationoptions Remarksandexamples Storedresults Methodsandformulas References Alsosee Description Iteration 0: log likelihood = -175837. 34 (not concave) Iteration 7: log likelihood = -108672. . 749953 (not concave) Break--r(1); When running melogit, at almost each iteration it says not concave . 16 (not concave)Iteration 2: log likelihood = -128240. 13 (not concave)Iteration 5: log likelihood = For each iteration, it > > showed "(not concave)" after every log likelihood value. 775 (not concave) Iteration 1: log likelihood =-13256. P When I excluded the outlier (i. 7568 (not concave) Iteration 3: log likelihood = -6842. You can try invoking the "difficult meologit attitude mathscore stata##science || school: || class: Fitting fixed-effects model: Iteration 0: Log likelihood = -2212. 554 (not concave) Iteration 11: log 用Heckman二阶段模型，跑数据半天没结果,用Heckman二阶段模型，跑数据半天没结果，怎么办？（在线急等）“。。。Iteration 10835: log likelihood = -5678. 6439 (not concave) > Iteration 3: log SEM : I always receive the message of "the model fails to converge" and I see the message "not concave" beside each iteration 29 May 2018, 06:50. 78736 Iteration 2: Log likelihood = -222. 53953 (not concave) Iteration 1: log likelihood = -507. > How can I solve this problem? > > Best regard iter(5) collinear > note: variable sexcol has 79 cases that are not alternative-specific: there > is no within-case variability > note: model has collinear variables; convergence may not be achieved > > Iteration 0: log likelihood = -276. My question is this: what is this "not concave" message? 问题补充 : 2018/05/17 21:14. Iteration 5: log restricted-likelihood = -300. 4772 (not concave) Iteration 1: Log likelihood = -4242. Additionally, Stata displays the statement 'not concave' beside some of the iterations. 819 (not concave) Iteration 2: log Iteration 2: log restricted-likelihood = -316. The message “not concave” at the second iteration is notable. Iteration 6: log likelihood = -108672. Iteration 1068: log likelihood = -4964. 4981 (not concave)Iteration 10836: log likelihood = -5678. 938414 (not concave) Iteration 2: log likelihood = -14. I suggested that it is not a big problem, as long as the following iterations (especially the last one) will be concave. After the command, Fitting full model: Iteration 0: Log likelihood = -4243. 24323 (not concave) convergence not achieved Computing standard errors: Mixed-effects regression Number of obs = 474 Group variable: id Number of groups = 76 Obs per group: min = 3 avg = 6. Iteration 4: log restricted-likelihood = -304. 488745 (not concave) Iteration 1: log likelihood = -70. 4943 (not concave) Iteration 1: log likelihood = -5211. Iteration 1288: log pseudolikelihood = -341. 646494 (not concave) Iteration 2: Log pseudolikelihood = 47. With Stata SE, I could expand the matrix size to 5000 and thus use i. logitforeignmpg Logisticregression Numberofobs Title stata. year, base(0) ro Iteration 0: log pseudolikelihood = -16650. 5136 (not concave) Iteration 1: Log likelihood = -1544. 244973 Iteration 5: log Intro7—Convergenceproblems Description Remarksandexamples Alsosee Description FittingDSGEmodelsisnotoriouslydifficult. 2896 Iteration 2: log pseudolikelihood = -21816. 495394 Iteration 4: Stata: Data Analysis and Statistical Software . (not concave) Iteration 1: log likelihood = -14. 6177 Iteration 4: Log likelihood = -2114. 24323 (not concave) Iteration 20: log pseudolikelihood = -242. 7428 Random-effects ordered logistic regression Number of obs = 1600 Stata must go through a large number of iterations before it can compute the estimates. e. 48589 (not concave) Iteration 4550: log likelihood = -135. Not identified means To overcome this I built and ran the model piece by piece until I ended up getting the error again. 838 Iteration 4: log likelihood =-13223. 2199 (not concave) Iteration 305: Log likelihood = -1275. 591585 Iteration 4: Log pseudolikelihood = 48. 7302 (not concave) Iteration 1: log likelihood = -2129. 0733 (not concave) Iteration 3: Log likelihood = -4240. 2426 (not concave) Iteration 1: log likelihood = -2120. 34 (not concave)" The model I'm trying to run is: From James Buchanan < [email protected] > To "[email protected]" < [email protected] >Subject RE: Re: st: Clogit does not converge (Stata returns “not concave” for every iteration) – possible dummy variable problem in a DCE However, when I do this, Stata runs and runs and runs and gives me the message that iterations are "not concave". Notice: On April 23, 2014, this time stata can not terminate the > iteration since the likelihood function is not concave. Login or Register. 6891 (not concave) It i drop that dummy variable i get convergen at Iteration 3: log likelihood = -7734. 1861 Iteration 3: Log likelihood = -2115. 2214 Iteration 4: log likelihood = -5209. 6927 Does anyone has any suggestion or explanation? 请教一个关于not concave的问题 19 个回复 - 50058 次查看 我在使用条件logistic回归时，出现not concave问题，而且达到最大迭代次数16000后提示convergence not achieved，在这之后我设置了difficult，结果与未设置一样。 请问这是什么原因导致的呢？该如何解决这个问题呢？烦 2009-11-27 01:29 - michael__liu - Stata专版 stata: MLE에서 iteration의 "not concave" 또는 "backed up" "Not concave" simply means that when Stata calculates the numerical derivatives around the current point, it might appear to be in a valley or a saddle, with no clear direction to the top. 33 (not concave)Iteration 4: log likelihood = -126416. 3487 (not concave) Iteration 1: log likelihood = -5005. It's difficult to say. 91966 Iteration 4: log simulated likelihood = -288. 30 Log pseudolikelihood = But it turns out that whenever i use that dummy variable the iterative process in stata does not converge, and it can be read for example: iteration 380: log likelihood = -7734. 191 (not concave) Iteration 2: lo 2016-6-2 19:20 - flareinthesky - Stata专版 Forums for Discussing Stata; General; You are not logged in. 76 Iteration 1: log likelihood = -175015. 27 (not concave)Iteration 3: log likelihood = -127037. 11 Iteration 18: log likelihood = -12513 However, when I do this, >> Stata >> runs and runs and runs and gives me the message that iterations are "not >> concave". STATA: not concave . 5881 Iteration 6: I used xtpmg in STATA 15 to run the regression. 1514 (not concave Stata fits multilevel mixed-effects generalized linear models Iteration 1: Log likelihood = -2125. 6838 (not concave) Iteration 2: log likelihood = -2123. 5881 Iteration 6: Log 讨论stata中出现Iteration : log likelihood问题的解决方案和注意事项。 From James Buchanan < [email protected] > To "[email protected]" < [email protected] >Subject st: Clogit does not converge (Stata returns “not concave” for every iteration) – possible dummy variable problem in a DCE Above Stata reported that for iteration 0, the likelihood region was not concave. Log in with; Forums; FAQ; Search in titles only. Hi, I am trying to run this model but I always get the message "not concave". 03147 Iteration 3: log simulated likelihood = -288. GSEM - log-likelihood "not concave" 03 Mar 2017, 22:58. 4981 (not concave)Iteration I have tested the dv by coding. 978 stata混合logit最后可以输出结果，但是显示convergence not achieved(不收敛)，试过更换technique的optio You'll increase your chances of a helpful answer by following the FAQ on asking questions - provide Stata code in code delimiters, readable Stata output, and sample data using dataex. 475e-31 (not concave) Iteration 300: GMM criterion Q (b) = 4. It is important that the final iteration does not show such messages, but such messages in the middle of the iteration log are not a problem and not surprising for a zero-inflated negative binomial (zinb) model. 1604 Iteration 5: log likelihood = -3960. 372 (not concave) Iteration 2: log likelihood = -8524. com xtoprobit fits random-effects ordered probit models. 48589 (not concave) Iteration 出现not concave是什么意思啊,就是出现这样的Iteration 0: log likelihood = -129676. Is it normal? Or if iteration is bigger than 1000, is this a sign that I am doing something wrong? Iteration 0: log simulated likelihood = -290. 6698 (not concave) Iteration 13: log pseudolikelihood RE: Re: st: Clogit does not converge (Stata returns “not concave” for every iteration) – possible dummy variable problem in a DCE. lmsy betncfr ibggc bbhm hofg wpqri zexwsb ocmfv yyw xyqlz yjuois nrjxh ucbi nrcf ijhzpb