KZbin recently changed the way my content will be monetised. My channel now needs 1,000 subscribers. So it would be amazing if you show your support by both watching my videos and subscribing to my channel if you haven’t done so already. Monetising my videos allows me to invest back into the channel with some new equipment so this small gesture from you will be extremely huge for me. Many thanks for your support….CrunchEconometrix loves to teach, help me stay online.
@josephndagijimana66105 жыл бұрын
Thank you
@cyrilchukwuka83784 жыл бұрын
Hello Ma how can I get to have a chat with you. Really struggling with my data
@CrunchEconometrix4 жыл бұрын
Hi Dipen, kindly search online for resources on this as I'm yet to have videos on this procedure. Thanks.
@elidetenga26624 жыл бұрын
This video gives the basis on my master dissertation! For real is perfect, it have clear content and illustration. THANKS A LOT
@CrunchEconometrix4 жыл бұрын
Thanks for the encouraging feedback, Elide. Deeply appreciated! Please may I know from where (location) you are reaching me?
@maeliank87965 жыл бұрын
This video may have just been the key to my bachelor thesis! Thanks a lot for the awesome content and the clear explanation! (coming from London) ;) will share in my university cause I know a lot of people struggling with this sensitive subject
@CrunchEconometrix5 жыл бұрын
Thanks for the positive feedback, Maelian...deeply appreciated! Happy to hear that you are willing to share the clip with your colleagues...gracias!!! :)
@Koreligozuyle4 жыл бұрын
I don't know how much I should thank to you for your effort and clear explanation!! I'm whipping myself to finish my thesis during self-quarantine and thanks to you I can proceed the analysis that I have been stuck. Your videos are not only helpful in terms of using stata technically but also understanding fundamental theoretically!
@CrunchEconometrix4 жыл бұрын
Thanks for the positive feedback and kind remarks. Deeply appreciated! Please keep safe! ❤️ May I know from where (location) you are reaching me?
@Koreligozuyle4 жыл бұрын
@@CrunchEconometrix Thanks for your comment back! I'm from South Korea, doing my degree in Turkey now :)
@cyruspatem88354 ай бұрын
Very interesting ma. You made me understand so very well 🎉
@CrunchEconometrix3 ай бұрын
Glad to hear that, deeply appreciated! 🥰
@claudiosfreddo32133 жыл бұрын
Hi Ngozi, I am refreshing my time series econometrics of non-stationary series and I can't stop watching your videos :-) Keep up the great work! Greetings from Switzerland - Claudio
@CrunchEconometrix3 жыл бұрын
Hi Claudio, thanks for the encouraging feedback. Deeply appreciated! 🙏 ❤️
@wanjadouglas30583 жыл бұрын
You just have a way of teaching and ensuring we get
@MrStaron475 жыл бұрын
your explanation is perfect!!!!! love it so much
@MrStaron475 жыл бұрын
Hi, I want to as you a question, why in 5:36, you only do the regression towards two variable lnpce and lnpdi, is there any reason why you don't include gdp on the regression?
@CrunchEconometrix4 жыл бұрын
Compliment is humbly taken, Fry! Thanks. May I know from where (location) you are reaching me?
@CrunchEconometrix4 жыл бұрын
Omission is deliberate. I could have included GDP if I wanted to. thanks for the observation, though.
@wzsun853 жыл бұрын
This video is a life-saver! When i run the ADF test, I dont know why the absolute t-statistic value is always smaller than the absolute critical value(no matter 1% 5% 10%), which is disappointing since i wanna reject Ho. Your video explained this quite clear and i got the ideal output(reject Ho and the variable is stationary) after using difference of log form, according to this video. Thank you !
@CrunchEconometrix3 жыл бұрын
U're welcome, WZ😊
@rao8559 Жыл бұрын
your accent is very soothing to the ears
@CrunchEconometrix Жыл бұрын
Hahahaha, Rao. Thanks for the warm feedback 😄
@aliuomotayosikiru61545 жыл бұрын
Wow! I find this useful without ambiguity. Kudos to you.
@CrunchEconometrix5 жыл бұрын
Thanks Sikiru, for the positive feedback...deeply appreciated! May I know from where you are reaching me?
@aliuomotayosikiru61545 жыл бұрын
But I have problem with my data, the Spurious reg. with 4 variables under study Indicate that R-squre is 0.5804 and durbin-watson is 1.7294. Which means that the variables are stationary but I tried to verify by conducting ADF and After conducting the ADF test, one of the variables are not stationary. What should I do?
@aliuomotayosikiru61545 жыл бұрын
Yea, I am a Nigerian, currently Studying MBA in Beijing Normal University, China.
@CrunchEconometrix5 жыл бұрын
@@aliuomotayosikiru6154 Drop it and use another close proxy.
@aliuomotayosikiru61545 жыл бұрын
@@CrunchEconometrix oops! But that variable (OPEC annual oil Price over 30 years) is really my interest. Or can I substitute it with monthly or daily price?
@ndoruhirweemmanuel73522 жыл бұрын
Many Thanks (From RWANDA - Kigali)
@CrunchEconometrix2 жыл бұрын
You are welcome, Sir 🙏. Much love from Nigeria ❤️.
@dipenmodi18075 жыл бұрын
Searching for a channel like this long time. Really good video though it's too brief. Like I didn't understand what lag is and why we use it here. Also, that trend and drift thing and how you generate the difference of the log variable.. I suggest you to please explain a little more in-depth as it really helps us beginners a lot. This channel is however the best one I found so far and I will definitely recommend it to others.
@CrunchEconometrix5 жыл бұрын
Hi Dipen, I'm humbled by your comments, thanks a lot. Please browse through my Channel of 102 videos and you'll see videos on "Optimal lag selection". By principle, I create brief and "straight-to-the-point" videos in series/parts....so as not to bore my viewers by limit most of my clips to below 15mins....keep watching and please share with your students and academic community...gracias!
@dipenmodi18075 жыл бұрын
CrunchEconometrix yes... Definitely! And thank you so much. I'll watch all your videos in these few days.
@ektasrivastava16784 жыл бұрын
Thankyou so much for the wonderful videos
@CrunchEconometrix4 жыл бұрын
U're welcome, Ekta. Please may I know from where (location) you are reaching me?
@sabihamarine44455 жыл бұрын
love your detailed presentation,,,,go ahead
@CrunchEconometrix5 жыл бұрын
Thanks Sabiha for the positive feedback!!! May I know from where (location) you are reaching me?
@pranayprateek67253 жыл бұрын
Your videos are really helpful. Great work.
@CrunchEconometrix3 жыл бұрын
Thanks for the positive feedback, Pranay. Deeply appreciated!
@fernandoanuno96873 жыл бұрын
Dear Ngozi, amazing for the explanation of the ADF Test through the youtube and very useful for my article. Thank you so much
@CrunchEconometrix3 жыл бұрын
You're most welcome Fernando!
@joev28263 жыл бұрын
Thank you so much!! It was clear and easy to understand!! 🎉💐
@CrunchEconometrix3 жыл бұрын
Glad it was helpful, Joe!
@joev28263 жыл бұрын
😍😍
@chelsealeibrandt52322 жыл бұрын
You teach so well! ❤️
@CrunchEconometrix2 жыл бұрын
Thanks, Chelsea for the encouraging feedback... deeply appreciated!
@jean-philippechen38775 жыл бұрын
Absolutely fantastic presentation of the content and explanation. Thank you so much
@CrunchEconometrix5 жыл бұрын
Thanks Jean-Philippe Chen for the positve feedback. Deeply appreciated! May I know from where (location) you are reaching me?
@rickymacharm98675 жыл бұрын
Discovered you yesterday. You are great. Nice to have a brilliant (Naija) sister doing us proud. I will tell my Econometrics class mate/colleagues about this site. Helped me out alot. Have you thought about doing such videos using open source programs like R and Python?
@CrunchEconometrix5 жыл бұрын
Thanks Ricky, at the moment I niche on the mostly used software. I will appreciate the publicity as many Nigerians are unaware of my KZbin Channel. My purpose is to let students and researchers know that econometrics is not as difficult as it seems. May I know from where (location) you are reaching me?
@rickymacharm98675 жыл бұрын
@@CrunchEconometrix I live in Abuja. I am more into Python and some R. Presently the Econometrics class is biased towards R. However your videos still opened my eyes to how to interprete the ACF, PACF, Augmented Dickey Fuller and so on. A real handy channel. Next week we Are moving into GARCH and the rest.
@gracediki21404 жыл бұрын
Soo helpful... am almost sybmiting my asignmnt, this z soo helpful thank yu
@CrunchEconometrix4 жыл бұрын
U're welcome, Grace! I'm glad you find this video very helpful. Please may I know from where (location) you are reaching me?
@gracediki21404 жыл бұрын
@@CrunchEconometrix Im in Zimbabwe
@kubilayuygur22623 жыл бұрын
Thank you for your perfect contribution. However, please clarify a little bit, why we use lag one instead of zero while performing ADF
@CrunchEconometrix3 жыл бұрын
Hi Kubilay, 0 lag = DF; 1 lag = ADF.
@laurasenke71983 жыл бұрын
Thanks so much for this. Really helpful
@CrunchEconometrix3 жыл бұрын
You're very welcome, Laura!
@wefunnygh25842 жыл бұрын
Your video is a life saver!
@CrunchEconometrix2 жыл бұрын
Thanks for the encouraging feedback. Deeply appreciated!
@gabrielcosteira17765 жыл бұрын
I just subscribed your channel... thank you for helping me out. Great job. By the way, I'm reading your website at this moment.
@CrunchEconometrix5 жыл бұрын
Hahahaha, thanks Gabe for giving me an excellent pass and for honoring me with your subscription. Grateful! 😀 May I know from where (location) you are reaching me?
@gabrielcosteira17765 жыл бұрын
@@CrunchEconometrix Wow, thank you!!! I'm from Brazil. Thanks for sharing your knowledge. I'm gonna indicate your channel to anyone who needs to implement an econometric model. Greetings! Obrigado
@oyku71972 жыл бұрын
thank you sooo much for this!! you are a lifesaver! btw do we need to take first difference in kpss test?
@CrunchEconometrix2 жыл бұрын
Thanks, Öykü for the encouraging feedback. Yeah, any stationary test will suffice but make sure you understand what its null hypothesis is.
@achudakhinkudachin20483 жыл бұрын
Great video! But how to know whether to first-difference or de-trend? That should also be covered by your excellent videos
@CrunchEconometrix3 жыл бұрын
Thanks for the positive feedback, Achudakhim. You may check other online resources for "de-trend" videos. Thanks.
@raifatou15 жыл бұрын
Thanks for the video. Very useful
@CrunchEconometrix5 жыл бұрын
U're welcome Raifatou......may I know from where you (location) are reaching me?
@raifatou15 жыл бұрын
@@CrunchEconometrix I'm in China. I'm doing my master's degree in agricultural economics and management.
@spinebuster94906 жыл бұрын
Thank you very much for this lesson. In eviews, it looks a bit complicated going through many levels.
@CrunchEconometrix6 жыл бұрын
The Art of The Deal Not at all, watch the EViews clip on that and you'll realize that it's easier than you think😊
@spinebuster94906 жыл бұрын
Absolutely. I will encourage others to subscribe.
@aplaexwdikio31904 жыл бұрын
I am writting from the UK, I wanna ask you something, how do you know how many lags you have to include? Do you test that through varsoc? One of my X in my regression is stationary at lag 1,2 but if I see through varsoc the optimal lag is 3, so when I am testing with 3 lags and no trend/drift it seems to be no stationary. but when I include a trend/drift with lag(3) it seems that it is stationary. From the graph I think the variable is stationary because I think it looks good. What it your opinion I hope I was clear, I wish I could send you the pictures of my panel from stata but I cannot here. Thank you for your time, I really appreciate your content.
@CrunchEconometrix4 жыл бұрын
Hi Apla, varsoc gives you optimal lags. No need to send the graph. Brief explanation will suffice. What technique are you engaging?
@bellisma7710 ай бұрын
As usual one if your greatest videos. I have a question plz which i could not understand, why test dfuller with lag 1? Does the sample size matter here? Thanx
@CrunchEconometrix10 ай бұрын
Using lag makes it the ADF test. Without lag, it's the DF test.
@camilloalborghetti9105 Жыл бұрын
Thank you very much for the amazing video, it is helping me a lot for my master thesis. A question I cannot aswer: what is the difference between L1 and LD''?Thanks again
@CrunchEconometrix Жыл бұрын
Thanks, Camillo for your encouraging feedback. Deeply appreciated. L1: first lag LD: lag difference
@mohammedalnour318 Жыл бұрын
Thank you dear Dr for the wonderful presentation. I have a question regarding the preliminary tests, when performing stationarity test, cointegration or cross-sectional dependence. From the empirical point of view, which is better to perform them before taking the log for the variables or after and why? Regards
@CrunchEconometrix Жыл бұрын
Hi Mohd, I use the log of the variables for these...on the "why"', I wil advise you scour the literature on any econometrics resource on the relevance of using the natural logarithm of a variable. Thanks.
@dgscholar Жыл бұрын
Hi ma'am, do I perform the optimal lag selection using AIC and BIC before the ADF test or after? Thank you in advance!
@CrunchEconometrix Жыл бұрын
Better to select optimal lags before testing for a unit root.
@collinchikwira78133 жыл бұрын
Thank you with your teachings..... can you assist with How to test for cross sectional dependence in stata
@CrunchEconometrix3 жыл бұрын
Collin, the video will be uploaded to my Teachable platform in due course. Here is the link cruncheconometrix.teachable.com
@collinchikwira78133 жыл бұрын
Thnks. Can you advice ...is it possible to report ...t test statistics and wald tests together undr one model .... can you help
@CrunchEconometrix3 жыл бұрын
Yes.
@RahmaBintNoor Жыл бұрын
if only you had a unit root test tutorial on panel data in stata. Please upload one
@CrunchEconometrix Жыл бұрын
Rahmata, watch my videos on panel ARDL. I covered 'stationarity test' on the series.
@shintaamalina3 жыл бұрын
Dear Dr. Ngozi. I am using Feasible Generalized Least Square (FGLS) for my panel data. Do I need to do ADF test? because Panel data consist of time-series data
@CrunchEconometrix3 жыл бұрын
Hi Shinta, yes.
@NhiLe-lr9es Жыл бұрын
Your video has helped me a lot with my thesis, I really appreciate your video
@CrunchEconometrix Жыл бұрын
Hi Nhi, if you untransformed the variable then it means the series is stationary at level with a trend. That is, I(0).
@NhiLe-lr9es Жыл бұрын
@@CrunchEconometrix Thank u so much
@richardchiponda61033 жыл бұрын
Hello Doc. Is it possible to ignore the trend and(or) the drift when running the ADF test.... So that the Command will just be like this =》 dfuller Var1, lags(1).
@CrunchEconometrix3 жыл бұрын
Yes. I only add trend if the series is nonstationary.
@richardchiponda61033 жыл бұрын
Thank you.
@immaculatelum51023 жыл бұрын
Thanks ma'am
@CrunchEconometrix3 жыл бұрын
Most welcome, Immaculate!😊
@gubulawallo12952 жыл бұрын
I appreciate u!!!
@CrunchEconometrix2 жыл бұрын
Thanks so much, Gubula! 🙏🥰
@makungupaschal47562 жыл бұрын
Thank you for this informative and educative video. In my data analysis, I have three variables; two are stationary after first differencing but one variable is stationary at level but not at first difference. What should I do ?
@CrunchEconometrix2 жыл бұрын
Hi, Makungu, watch my ARDL videos. That's your next step.
@chimukamondemulala2 жыл бұрын
How do you fix the 'repeated time values' error? Can't find the solution.
@CrunchEconometrix2 жыл бұрын
Chimuka, that happens when you are using a panel data to estimate a time series analysis.
@elormbismark47523 жыл бұрын
Hi Doc, Thanks loads for your indepth but simple to understand tutorials. Doc, can you kindly help. So I am using to 3 variables for an analysis. For 2 of the variables, the raw time series data are stationary without differencing. But the 3rd, variable is stationary at first difference. Can go ahead and run the model on the raw values of 2 the two variable together with the first difference of the 3rd variable??
@CrunchEconometrix3 жыл бұрын
Hi Elorm, on what to do, kindly watch my video on "This is how to specify ARDL models". Afterwards, watch my videos on the Bounds Test followed by other ARDL/ECM videos.
@ds--2 жыл бұрын
Great Video, however I am struggling with the time series part, as it says the dates I've used are 'string variables'.
@CrunchEconometrix2 жыл бұрын
Hi Dominic, convert to numeric variables stored as "byte, int, long, float or double". I advise you check out other online resources on how to do this. Thanks.
@622948383 жыл бұрын
I am not so sure if DW test of serial correlation has anything to do with R-square and let alone Unit root and DF distribution, please may I ask where can I find the existing source of such information?
@CrunchEconometrix3 жыл бұрын
Hi GG, I don't know what to make of your query but you search online for resources that addresses your quest. Thanks.
@michealmerlin84013 жыл бұрын
hello i have a question. what should i do if the variables are still not stationary even after using the first difference. thanks in advance :)
@CrunchEconometrix3 жыл бұрын
Hi Micheal, I will advise you drop it and use a closer proxy.
@alichowdhury61912 жыл бұрын
Thank you so so much! I'll definitely include you in my prayers! I just had one question, when i tested for the first time, it was non stationary, but when i tested with the 1st differences of the variables, it showed me that it was stationary. So do I conclude that the variables are indeed stationary?
@CrunchEconometrix2 жыл бұрын
Hi Ali, please know that all I(1) series are NONSTATIONARY. Reason: you had to difference it before it became a stationary series. You can also say it's nonstationary but stationary after 1st difference.
@thuongvu25032 жыл бұрын
Thanks for your great video. I am writing from Germany. Pls kindly advise me a question as below: My model has 8 variables (1 dependent and 7 independent) with annual data in the period of 31 years. When I draw the graph of variables, some of them show a clear trend, so I use command: dfuller [varname], trend lags(1) => okay. But I have 2 cases that I don't know which command I should apply: (1) some variables don't show a clear trend, at first they declined within the first 20 years, then they stayed quite stable in the last 10 years. (2) some variables don't show any trend, they fluctuated over time (stochastic). Which command should I apply for 2 cases above pls? dfuller [varname], lags(1) Or dfuller [varname], drift lags(1) Or dfuller [varname], nonconstant lags(1) (I mean the option: suppress constant term in regression) Hope to hear from you soon.
@CrunchEconometrix2 жыл бұрын
Hi Thurong, I always start with option 1.
@thuongvu25032 жыл бұрын
@@CrunchEconometrix hi, do you mean that dfuller [varname], lags(1). Right?
@CrunchEconometrix2 жыл бұрын
@@thuongvu2503 Yes
@neyaleedas45743 жыл бұрын
The series at first difference level becomes stationary only when we included the drift term. It is still non stationary when the constant term is suppressed or the trend is concluded. What does it say for the series over all - stationary or non stationary?
@CrunchEconometrix3 жыл бұрын
Neyalee, don't suppress the constant term. Series is stationary with a drift.
@debosmitachatterjee99942 жыл бұрын
Hi! Many thanks for the video. It was immensely informative. Please may I ask you a question? I have an unbalanced panel dataset. Do i need to convert it to a balanced dataset before running panel regressions? Thank you so much and any advice you offer is highly appreciated.
@CrunchEconometrix2 жыл бұрын
Hi Debosmita, you posted your query on a WRONG video. This is NOT a panel data video. Kindly re-post correctly. Thanks
@debosmitachatterjee99942 жыл бұрын
@@CrunchEconometrix so sorry..
@bangladeshisoulsinuk49932 жыл бұрын
Hi I have a panel unbalanced data, i used fisher type test only on dependent variables, like female labour force. I can see I have unit root. what am I supposed to do to remove it. Also do I need to check all my independent control variables as well ??
@CrunchEconometrix2 жыл бұрын
Kindly watch my videos on panel ARDL. I covered stationary test and other specifics. You will find them helpful. Thanks
@bangladeshisoulsinuk49932 жыл бұрын
@@CrunchEconometrix thank you very much, is there a chance I could ever chat with you?
@bangladeshisoulsinuk49932 жыл бұрын
I have used first difference but my R2 becomes very very low. 0.0015.
@CrunchEconometrix2 жыл бұрын
You didn't pay attention to my response. I indicated what you need to do. Watch my panel ARDL videos.
@okunlolaacademy86822 жыл бұрын
when it was not stationary at first, you created the difference. how did you get the figures for the difference
@CrunchEconometrix2 жыл бұрын
gen dlnpce=D.lnpce
@okunlolaacademy86822 жыл бұрын
Thank you Dr. Will try this and revert. And, please, do you do this for all data that exhibit similar outcome ma.
@CrunchEconometrix2 жыл бұрын
Yes. If the series is nonstationary at level.
@freddygonzalez99922 жыл бұрын
You save me
@CrunchEconometrix2 жыл бұрын
Awww Freddy, glad to be of help 🙏🥰
@ektasrivastava16784 жыл бұрын
my R sq. value is 0.98 and watson statistic value is 1.92... does this means , i do not need to perform the stationarity test?
@CrunchEconometrix4 жыл бұрын
Hi Ekta, performing the stationarity test gives you the confidence required to proceed in time series analysis.
@josephazumah70323 жыл бұрын
Please how do I generate the difference variables
@CrunchEconometrix3 жыл бұрын
Hi Joseph, use this syntax: gen dy = D.y
@MidheksaDeneka Жыл бұрын
thanks a lot
@markcahucom1675 Жыл бұрын
I noticed that lnpce has the letter D beside it making it D.lnpce. What does the letter D mean?
@CrunchEconometrix Жыл бұрын
Hi Mark, it means "1st Difference " OR "Change".
@markcahucom1675 Жыл бұрын
@@CrunchEconometrix thank u so much for the reply. Love your channel as well as the content. Much love!!! ❤
@CrunchEconometrix Жыл бұрын
Thanks, Mark for your encouraging feedback. Deeply appreciated!🥰🙏
@kunswelo3 жыл бұрын
hello, how do you make the first difference?
@CrunchEconometrix3 жыл бұрын
D.variable
@bolarinwaajanaku13446 жыл бұрын
Hi, thank you for this video and very easy to comprehend. Please, I have a quick question to ask you. If I do the stationarity test and my variable becomes stationary at the first difference, am I going use the data in the first difference to run my regressions or I can still use data at the levels to run the regressions
@CrunchEconometrix6 жыл бұрын
Thanks Bolarinwa for the kind comments. For your query, I'll refer you to my videos on VAR and ARDL Models. If you are using the VAR and ARDL algorithms, you enter the variables in their level forms but if you're using the OLS algorithm, then you use the 1st difference of the series.
@lilianacusicanqui22064 жыл бұрын
Thank you! amazing videos with a clear explanation! :D One question tho. I appreciate you could help me, please. D. Watson test confirms it's a stationary model but ADF shows the different answers. So after the first differential, some variables are stationary and others keep being non-stationary. Should I differentiate them once more? And then, should I run all the model with these new second differentiated variables?
@CrunchEconometrix4 жыл бұрын
Hi Lilliana, thanks for the positive feedback. Deeply appreciated! DW is not used to determine stationarity. Kindly watch the clip again and follow my interpretation. Please may I know from where (location) you are reaching me?
@m.walidhemat63193 жыл бұрын
Hello, In my case, all variables are stationary at level when I select drift term, but they are not stationary when I select trend term Also D.Watson is smaller then r square. Now, can I proceed with this data?
@CrunchEconometrix3 жыл бұрын
Hi Walid, you decide if you want to include a trend or not and then take your analysis from there. Regards.
@maryashaheen31 Жыл бұрын
Mam can we increase the lag to2 while using ADF test in order to make my variable stationary or we have to maintain the lag value to 1
@CrunchEconometrix Жыл бұрын
Yes, Marya, you can.
@maryashaheen31 Жыл бұрын
@@CrunchEconometrixmam can you please help me with narrative citation in ms word without using Mendeley.
@CrunchEconometrix Жыл бұрын
Hi Marya, MS Word had an inbuilt citation menu that you can use. Also, do a Google search for citation software. There are thousands of them.
@vaneberlot5 жыл бұрын
Hello, In case I use ADF including 1 or 2 lags, none of my first difference variables become stationary. Is it ok if I use classic DF test and phillips-Perron stationarity test? In case I do not include lags in stationarity test, shall I use lags when checking for coiintegration and testing VECM ? Thanks for the answer.
@CrunchEconometrix5 жыл бұрын
Hi Vane, if you use lags then you are performing the ADF. Without lags it is just the DF test. It is also ok to use the PP test. Yes, include lags when testing for cointegration and reduce the lags by 1 for the VECM (watch my videos on that).
@shintaamalina3 жыл бұрын
Dear Ngozi, thank you for the great video. It's very helpful. I have question about how to transform the data into difference form? the difference is transformed from the original data or from the log data? Thank you!!
@CrunchEconometrix3 жыл бұрын
Shinta, that will depend on the form of the variable. Difference can be obtained both ways.
@shintaamalina3 жыл бұрын
I see. I tried to run my data again. Now the t-statistic is greater than the 5% critical value. But the constant value still not significant. How to deal with this? 🙏🙏
@CrunchEconometrix3 жыл бұрын
Constant is the intercept of the model. My advise is that you support video tutorials with reading econometrics textbooks with Sections 3 and 4 of articles that used the technique. It is the best way to understand and interpret results.
@ngantranthuythuy8573 жыл бұрын
Hi, i have a question: How to create a dialogue form of a variable?
@CrunchEconometrix3 жыл бұрын
Hi Nga, I honestly have no idea what a "dialogue form" is.
@fuzhufeifei5 жыл бұрын
Dear Ngozi, for first differenced variables, I didn't include trend term because some information (long term information) has been removed after first difference. First differenced data will not have long-term information any more. In this case, we would not expect that such variable has a trend. So I think that it is better not to include trend term when we do ADF or PP tests for first differenced form. How do you think?
@CrunchEconometrix3 жыл бұрын
Most times, I perform URTs w/o a trend Unless the series is nonstationary then I include a trend in the 1st difference.
@nanakwakubour-donkor26943 жыл бұрын
Dw= 1.976556 and r^2=0.4179 but 3 out of 4 independent variables are not stationary according to augmented Dickey fuller test. What is the problem here?
@CrunchEconometrix3 жыл бұрын
Make the series stationary and re-estimate.
@ssenyonjobills4473 Жыл бұрын
Show me how you performed the difference dlnpce and the rest.....
@CrunchEconometrix Жыл бұрын
Ssenyonjo, watch the video to see what I did. Thanks
@raihansiddika99424 жыл бұрын
Hi, Why did you use 'trend' in the first differenced series? since the plot of the first difference series does not show any trend, isn't it wrong to use 'trend' option in the ADF test for that first differenced series?
@CrunchEconometrix4 жыл бұрын
Raihan, it is not wrong to use the trend option.
@fatimazahramoussaid3503 жыл бұрын
Hello, please does the fact of choosing 1 lag gives different results because in eviews 10 they set number of lag by defaut at 9 ?
@CrunchEconometrix3 жыл бұрын
Hi Fatima, modify the lag structure.
@Lost113854 жыл бұрын
The video is applicable in case of time series data only or the same steps are applicable to panel data as well ? Plz clarify.
@CrunchEconometrix4 жыл бұрын
You can use it for panel analysis too.
@hehaisong43535 жыл бұрын
Hi Cruch Econometix, I have a question: The final regression table shows the constant coefficients. May I know do I need to input this constant coefficients later on at the ARIMA estimation stage (the other tutorial video), where there is a table to input p,d,q and there is also a cell to input constant. May I know is the constant coefficients need to be keyed into the cell? Thank you!
@CrunchEconometrix5 жыл бұрын
He, your queries are confusing. Kindly post respective queries on the videos concerned not lumped together. This video is on ADF not ARIMA. Thanks.
@peterdavidkulyakwave61026 жыл бұрын
Thanks madam for such a pretty presentation. Please, assuming this ADF is already assured as you end up. Then my question. If i needed to perform estimates with the series what data are going to be employed in the model? Are the one differenced for ADF test or the original data. To put it abit clear: estimate people's consumptions using cpi as independent as your data dictates. So, you hav successifuly checked for stationarity, then which data set will be used in your regression model? Please?
@CrunchEconometrix6 жыл бұрын
Hi Pete, there's still a lot of contention as to whether you use the raw or differenced variables for the regression. But I've always maintained that you used the raw variables if you are using the VAR or ARDL algorithm to estimate the models and you use the differenced series if you're using the OLS algorithm. Others may contest this, but this is my approach. You can always check Gujarati and Wooldridge or any econometrics text to see how time series models are expressed.
@peterdavidkulyakwave61026 жыл бұрын
CrunchEconometrix kindly, Thanks inadvance I wan check also in the proposed books on time series hints.
@nicolalampis65243 жыл бұрын
Why it is not correct to put Olags in the ADF test? I did not understand your explanation for that
@nicolalampis65243 жыл бұрын
0 lags*
@CrunchEconometrix3 жыл бұрын
Nicola, 0 lag = Dickey-Fuller test. With lag = ADF test.
@samarhussein57893 жыл бұрын
YOU ARE THE BEST :)))
@CrunchEconometrix3 жыл бұрын
I'm encouraged, Samar😊...thanks!
@user-dy7hg3vs3g4 жыл бұрын
thanks for the video. A quick question - is performing a Dickey-Fuller test enough to confirm a variable is stationary? can we assume a variable is stationary in mean, variance, and covariance if it doesn't have a unit root?
@CrunchEconometrix4 жыл бұрын
You have just defined stationarity.
@ShlaghaRastogi3115 жыл бұрын
Hi! I just found this video, it's amazing and your way of explaining things is impeccable. Just one doubt though, at 9:30, you said the absolute value of test statistics is not greater than any of the available options of the absolute value of critical values, it didn't seem right to me. 1.436>1.292(10%critical value) So this should mean that lnpce is stationary at 10% critical value or is 90% stationary? Please let me know if I am thinking right. Thanks!
@CrunchEconometrix5 жыл бұрын
Thanks Shlagha, for the positive feedback. Deeply appreciated! I mentioned that the series is nonstationary at the 5% level. However, it is stationary at 10%. May I know from where (location) you are reaching me?s
@ShlaghaRastogi3115 жыл бұрын
@@CrunchEconometrix Oh now I get it! Thanks! I am from India, by the way :)
@CrunchEconometrix5 жыл бұрын
@@ShlaghaRastogi311 Awesome! I'll appreciate it if you can share the link to my KZbin Channel with your friends and academic community in India 🇮🇳 for awareness...thanks 😊.
@ShlaghaRastogi3115 жыл бұрын
@@CrunchEconometrix Sure I will! :)
@manuellatonga37622 жыл бұрын
when we put zero to test of dickey fuller, it does not mean that we are a level? because you put one, and conclude that is not stationnary, but not stationnary in which level? level or first difference?
@CrunchEconometrix2 жыл бұрын
Manuella, please read up on STATIONARY TESTS to know the differences between level- and difference-stationary series. If you estimate at any lag you can either get a level-stationary 1(0) or a nonstationary series I(1).
@michelliasantosa84782 жыл бұрын
Is performing ADF Test for Panel data the same? If not, do you have any references?
@CrunchEconometrix2 жыл бұрын
Hi Michellia, the ADF algorithm for panel data is different. You can do a Google search on it for details and references. Thanks.
@priyeshjammula8544 жыл бұрын
Can you please tell me what kind of variable is qtrly? It's howing me as a string(as it contains letters and numbers) hence not able to use it along with tsset command. Would appreciate if you could tell me where I am going wrong. Thank you.
@priyeshjammula8544 жыл бұрын
Got it how to be done. Thank you for these videos. Worth appreciating!
@CrunchEconometrix4 жыл бұрын
Thanks for the encouraging feedback, Priyesh. Deeply appreciated! Please may I know from where (location) you are reaching me?
@priyeshjammula8544 жыл бұрын
Yeah sure:) It's New Delhi, India.
@yanuozhou6028 Жыл бұрын
Hello sir, does lags(1) correspond to "betaLNPCE t-1" in the regression model? varsoc gave me the optimal lag length of 4, should i put in "dfuller, X1 lags(4)" ? Also, would my model look like this: "betaX1 t-4" if i want to do ARDL modeling? (assuming X1 is stationary at level with lags(4)). Thank you!
@CrunchEconometrix Жыл бұрын
Yanuo, the answer to your 1st and 2nd queries is YES. For the 3rd, watch my video to see what I did and adapt your model.
@yanuozhou6028 Жыл бұрын
@@CrunchEconometrix Thank you so much!
@teddykim4305 жыл бұрын
Thank you for posting this video! I have two questions: Do I have to test if all my variables (3 independent and 1 dependent variables) with the ADF test? If some of my variables are stationary and some are non-stationary, can I still use time-series analysis or do they all have to be stationary?
@CrunchEconometrix5 жыл бұрын
Yes Taekyun, perform ADF test on each variable and YES only stationary variables are allowed in TS analysis....may I know from where you are reaching (location) me?
@burakcanersevimli93644 жыл бұрын
Thank you for your lessons, but i have a problem. How can i determine intercept and trend value ?
@CrunchEconometrix4 жыл бұрын
Hi Burak, thanks for the positive feedback on my video. The coefficients for trend and intercept are indicated in the ADF Table as shown and explained in the video. Please may I know from where (location) you are reaching me?
@valensrwema4 жыл бұрын
Hi thank you for this fantastic video i am very happy for this tutorial but i have a question about how to create differences in order to perform the unit roots test when it is not stationary at level, thank very much
@CrunchEconometrix4 жыл бұрын
Hi Valens, thanks for the positive feedback. Deeply appreciated. Watch the video to the end. I did just that. Please may I know from where (location) you are reaching me?
@gyuldzhankozumali23006 жыл бұрын
Hello CrunchEconometrix! The video is quite helpful, thank you for that! I have few questions: 1. When I check for trend, my graph is quite chaotic but the values don't intercept. is that a problem? 2. When I try to perform the DW test, an error with this warning occurs "sample may not include multiple panels". In the error code stata provide it says i'm trying to test something that doesn't make sense, but doesn't tell me what exactly. What exactly its trying to tell me and hw should I fix it? Thank you in advance! :)
@CrunchEconometrix6 жыл бұрын
Hello Gyuld, I have read your query over and over but still have no idea as to what the issue is. This video comment is for the augmented Dickey-Fuller (ADF) test, so can you be more explicit?
@victoriafadare26594 жыл бұрын
Thanks so much for your videos, they are so helpful. I have a question - Does the rule of when the R^2 is greater than the Durbin Watson d-statistic the variables are non-stationary still hold when using multiple variables. For example, if I were to perform a regression with 6 variables. Would it be okay to draw the same conclusion? If not, how would I prove the variables are stationary when there are multiple variables.
@CrunchEconometrix4 жыл бұрын
Hi Victoria, thanks for your encouraging feedback. Deeply appreciated! Yes, same rule applies. Please may I know from where (location) you are reaching me?
@victoriafadare26594 жыл бұрын
CrunchEconometrix I’m from the UK Thanks for the reply and once again your videos are amazing and very helpful, looking forward to more.
@CrunchEconometrix4 жыл бұрын
No worries, I'll keep doing my best...thanks!
@felixpattinson6 жыл бұрын
Thanks for the video, what if we are using more than two variables? How are we performing the durbin Watson and the adf tests?
@CrunchEconometrix6 жыл бұрын
Hi Felix, thanks for watching my videos. The ADF test can be used on as many variables as possible because you are basically testing each variable for the presence of a unit root. The Durbin-Watson test is a post-estimation test obtained after you have carried out a regression analysis (whether univariate, bi-variate or multi-variate). If my videos have been helpful, I'll appreciate if you tell others about my Channel...thanks!
@seanh199545 жыл бұрын
Hi, how do we pick the optimal lag variable for a ADF test if a lag of 1 already shows that you'd dont reject H0 (implying that is is non-stationary)
@CrunchEconometrix5 жыл бұрын
Take the 1st difference of the series and test for stationarity.
@thetruth47124 жыл бұрын
Hi, thanks for this useful video. I have one question to ask, do we need to run var model even our data are stationary at level form?
@CrunchEconometrix4 жыл бұрын
Hi Toba, thanks for the positive feedback. Not VAR, just the OLS technique.
@xuewang23375 жыл бұрын
Hi, I have a question on how to determine the lag numbers in ADF test. May I confirm to determine the lag number, I perform the Varcos [var] in STATA, correct? I performed varcos [var] in STATA, and chose AIC as a criteria. My data is monthly data, and I got an optimal lag number 4. Is this reasonable, as you have mentioned that for monthly data, the lag number is usually 6, 12 etc. This lag number is different from the ARIMA (p,d,q) am I correct? Thank you so much!
@CrunchEconometrix5 жыл бұрын
Hi Liu, once any IC chooses the optimal lag, you stick with that. It is the same as the "p" referred to in ARIMA.
@xuewang23375 жыл бұрын
@@CrunchEconometrix hi, but my arima p is zero. my SARIMA is (0,1,1)(0,1,1,12). Is anything wrong?
@alessandralima41656 жыл бұрын
Hi, kindly may I ask you for the academic references for your rule of thumb that since the absolute value of the Test Statistic (1.726) is lower than the absolute value of the 3 options (4.071, 3.464, 3.158) ...we can not reject the null-hypothesis (|phi| =1) or as you say . Nice vid, suscribed time ago. Greetings.
@CrunchEconometrix6 жыл бұрын
Hi Aless, you can always refer to any econometrics textbook on the rudiments of stationary where you read about whether a series is stationary or not....in addition to several journal papers for the interpretation of stationarity. Hope these suggestions are helpful. Thanks!
@fuzhufeifei5 жыл бұрын
Hi, dear Ngozi, what's the meaning of "include drift term in regression?" does it mean that we are now using the first-differenced form to see whether the variable is stationary or not?
@CrunchEconometrix5 жыл бұрын
If you think your series exhibits a drift, then include it in your regression. Otherwise, not necessary.
@larryanifowosed76285 жыл бұрын
Secondly, i used the reg command, i found my Durbin-Watson d-statistic = 1.407865 and R-squared = 0.5235. what should i do ?
@CrunchEconometrix5 жыл бұрын
Why use reg command? Did you test for unit root?
@tashilaethenpa43174 жыл бұрын
Hello I have been watching your video series on GMM and its been a great help ..........well could you guide if unit test is a requirement of the variables when i intend to use GMM model and in case required, which test i should go for? .......thanks
@CrunchEconometrix4 жыл бұрын
Hi Tashila, thanks for the encouraging feedback. Deeply appreciated! Kindly watch my 9 GMM series for more information on the procedure. I covered most of the basics. Please may I know from where (location) you are reaching me?
@tashilaethenpa81394 жыл бұрын
Tashila Ethenpa I am studying in Tokyo,Japan but basically from India
@MazeedMukhtarOyeleye7 ай бұрын
My time-series dataset is still showing stationarity after the first difference 😭 What can I do, ma'am?
@CrunchEconometrix7 ай бұрын
You can do several things: increase the lag length when performing the unit root test OR change the variable to a closer proxy.
@MazeedMukhtarOyeleye7 ай бұрын
@@CrunchEconometrix Many thanks, ma'am I've tried using up to 8 lags, same story 🤧 I'd try using another proxy too
@CrunchEconometrix7 ай бұрын
For time series analysis, the unit root test is done on each variable. Do you mean all the variables are NOT stationary after the 1st difference? That would be a very strange occurrence.
@MazeedMukhtarOyeleye7 ай бұрын
@@CrunchEconometrix Yes, ma'am. I have 4 independent variables and 3 control variables. Alongside the dependent variable, only a few of them were stationary at the same lag, even at the first difference. So, I opted for quarterly data instead, and they are now stationary at the first difference
@goncalosilva81554 жыл бұрын
Thank you very much for this video. I do have a question though. Is it a problem if my variable is still nonstationary when including the trend but stationary when including the drift?(i am using the first difference so, I'm not doing that part wrong) Edit: my variable is ln of real GDP in quarterly data
@CrunchEconometrix4 жыл бұрын
Hi Silva, thanks for the positive feedback on my video. Deeply appreciated! This is not a problem. Simply indicate on the Table of results that the series is stationarity with a drift then proceed to estimation. Please may I know from where (location) you are reaching me?
@goncalosilva81554 жыл бұрын
CrunchEconometrix hello again! I am writing to you from Lisbon but am currently studying at the university of Nottingham! Let me take this chance to once again thank you for the clarity that you provide with your step by step analysis in your videos. It really is a game changer and has already answered a few of my many questions related to my thesis 😅. Thank you and God bless you
@carlosvaz63386 жыл бұрын
Thank you for your explanation. It was easy to undestarnd. Just one question: What could I do if my data had a clear seasonal pattern or/and strutural breaks?
@CrunchEconometrix6 жыл бұрын
Thanks Carlos for the compliments. For structural breaks, the Zivot and Andrews (1992) test for unit root will be the most applicable as their test is an improvement of Perron (1989)’s. They assume that the exact time of the break-point is unknown so their method endogenously identifies the breakpoint. Likewise, the Gregory and Hansen (1996) test is designed for cointegration testing when controlling for structural breaks. Do you use Stata?
@carlosvaz63386 жыл бұрын
Thanks for your quick reply. Yes I do!
@CrunchEconometrix6 жыл бұрын
No worries...please tell others about my channel!...gracias!!!!
@widyarininasya73085 жыл бұрын
You should make a dummy variable
@spencerclark19256 жыл бұрын
Hi, thanks for the very informative and easy to understand video. I am trying to conduct the ADF test on some time series data. I have two questions. 1. The literature emphasises the importance of choosing the optimal lag length. I have used varsoc to help me for each variable, how do I then add this to the test? 2. Say my data has a clear time trend at level after looking at the plot. If it is non stationary at level, and then I use instead the first difference, do I still select the trend when doing the ADF test for the first difference. Kind Regards, Spencer
@CrunchEconometrix6 жыл бұрын
Hi Spencer, thanks for the kind words and I am indeed glad that I have the opportunity to teach the little I know using this medium. For the 1st question, use this code: dfuller d.y, trend lags(1)....for 1st difference stationarity test. For the 2nd question, yes you can include the trend option if graphical plot of the series shows that it has a trend. Use this command: dfuller d.y, trend lags(1)....for 1st difference stationarity test. Remember, the choice of lags is from the outcome of "varsoc". Initially run the test using 1 lag, then 2. But not more than 2 so as not to bias your test. Result is acceptable If the series is stationary at 1st difference with 1 lag even if the optimal level is 2 or more. Hope this explanation helps.
@spencerclark19256 жыл бұрын
CrunchEconometrix Thank you for the reply, I am trying that out now! Just for clarification. First with just the level data. Say that the recommended lag is 2. I conduct the ADF test with following code dfuller var1, trend lags(2) ?
@spencerclark19256 жыл бұрын
And if I cannot reject the null of a unit root, I then conduct the ADF test on the first difference. So I find using varsoc for that first difference variable the lag is now 1. Do I use code Dfuller dvar1, trend lag(1) ?