Check out the GenAI powered multi-lingual version of this same video here : ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-wz4lbSK07Tg.htmlsi=1xA1SP7MZiuH8_vu
On topic of misunderstandings : Wife texts husband on a cold winter morning: "Windows frozen, won't open." Husband texts back: "Gently pour some lukewarm water over it and then gently tap edges with hammer." Wife texts back 10 minutes later: "Computer really messed up now."
If you liked this video you may also enjoy this other explainer videos on Wicked Problems Kennisland-How To Work With Wicked Problems ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-HrWbicvDLPw.htmlsi=eUvg7T16_D-nIltW
Check out my sequel video where I walk thru a Python based approach medium.com/analytics-vidhya/building-a-probabilistic-risk-estimate-using-monte-carlo-simulations-with-python-mcerp-7d57e63112fa
Hello Zhijing Eu, thanks for your kind effort. Im trying to practice the simulation by watching your video. I've used the same variables and the same values like yours. I've installed the XLRisk correctly. However, my resluts shows no outputs, no graphs but inputs only. Could you please guide me to solve the issue? Thanks in advance.
Hey Zhijing, firstly, this is amazing and very helpful. Thanks for the content. It made life easy. One thing I can't get my head around is how the correlation matrix works in understanding those values and attributing them to the elements. I have gone through your links posted for more examples and answers in the comments yet I can't seem to wrap my head around it. How does the risked value lets say in accommodation, understand that there is a correlation of 0.85 between its value and the value of meals. I do not see any link in those tabs. The function reads numbers from a table that do not have the elements linked. I might be super confused, but I've been scratching my head around this a lot. Hope you can help...
Can you help me with something? I'm getting the following error with corr matrix: "The table (referenced) doesn't have all off-diagonal values between -1 and 1". The thing is that it is, and there is nothing on githup about how to deal with it.
Under the tab Uncertain Range+Events+Corr, there is a table in cells G14:I16 that represents the correlation matrix. Maybe you accidentally changed the values in the non diagonal cells? (H14, I14, G15, I15, G16, H16)
@@CH2CH2CH2 Your is perfect, I'm using another one, the values for the correlation differ from -0,27 to 1 with 19 variables (diagonal all 1), I've tried to change the numbers and reduce the 19 but receive the same message.
Hmmmm... This is tricky. First try to set the non diagonals as zeroes just to see if it still runs and it's not an XLRisk problem. If not then it could be that the correlation matrix is inconsistent. kb.palisade.com/index.php?pg=kb.page&id=75 Unfortunately unlike commercial software like @Risk or Frontline Solver which have Auto Corr matrix adjustment tools, you might have to find a way to use Python to calc the eigen values... if you know a bit of coding you might be able to apply the method described here to adjust your coefficients community.wolfram.com/groups/-/m/t/1078904
Try these stackoverflow.com/questions/10939213/how-can-i-calculate-the-nearest-positive-semi-definite-matrix or stackoverflow.com/questions/43238173/python-convert-matrix-to-positive-semi-definite
Hello Zhijing Eu, thanks a lot for your video. i try to use monte carlo for QMRA. Is it true if i say graph cummulative distribution describe about variability? I found out about how to make uncertainty with monte carlo, and it said that i need to second-order. But i confused about parameter input that i use in second-order. And i cant find Tornado diagram in my XLRisk. i use 2 parameter input for my output. does it affect the output of the diagram?
Hey Zhijing, can you show it again how you linked the correlation matrix with results in I4:I9. I am getting following message when I try to run simulation. "The risk functions have not been properly linked to the correlation matrix".
In the tab Uncertain Range+Events+Corr, there is a matrix in cells G14:I16. This is referenced in the risked ranges in cells I4 to I9 via the ",RiskCorrmat" suffix to the risk distribution being used. Read the help documentation for more examples github.com/pyscripter/XLRisk/wiki/CorrelatedInputsExample
Tx Zhijing, but you must have done something in addition to RiskCormax in order to enhance the correlation. I see that cells in I4:I9 are named i.e., I5 is "AccomCost" etc... Have you connected it somehow to Corr matrix?
You need to ensure you name the range for the Corr matrix but also specify which variable you are referring to i.e I5 Accom Cost is ", RiskCorrmat($G$14:$I$16,1)" , I6 Meals is ", RiskCorrmat($G$14:$I$16,2)" and I8 Holiday Tours is ", RiskCorrmat($G$14:$I$16,3)"
You can run Monte Carlo Sims using just Numpy and Scipy. However this can be a a bit tedious to set up so there are a few Python Libraries that simplify this process in terms of providing more choices for sampling methods, managing sub-simulations and summarising the results PyMCSL pymcsl.readthedocs.io/en/latest Monaco monaco.readthedocs.io/en/latest MCerp github.com/tisimst/mcerp There are lots of examples online if you do a general web search. However most tutorials skip a critical element - how to induce rank correlation between the random input variables. Without this, the simulation will assume that all input variables are independent and uncorrelated which is usually not reflective of most modelled phenomenon. Therefore simulation outcomes will end up underestimating the variability due to the Central Limit Theorem statisticsbyjim.com/basics/central-limit-theorem/ However I can recommend this one example that does cover the use of correlated variables using MCerp : towardsdatascience.com/journey-to-monte-carlo-mc-simulations-with-correlated-variables-in-python-1aef84d5742d
@@shiwaninaik3935 glad I could help. I'm planning to redo this tutorial video using Python instead of XL Risk when I get a bit of time later this year so stay tuned.
In the tab Uncertain Range+Events+Corr, there is a matrix in cells G14:I16. This is referenced in the risked ranges in cells I4 to I9 as a ",RiskCorrmat" suffix to the whatever risk distribution is being used. Read the help documentation for more examples github.com/pyscripter/XLRisk/wiki/CorrelatedInputsExample
FYI only if you are stuck trying to replicate this and getting an error when calling GPTSimpleVectorIndex, it is because a few months after I published this, LlamaIndex renamed GPTSimpleVectorIndex to GPTVectorStoreIndex github.com/jerryjliu/llama_index/issues/1900
FYI only if you are stuck trying to replicate this and getting an error when calling GPTSimpleVectorIndex, it is because a few months after I published this, LlamaIndex renamed GPTSimpleVectorIndex to GPTVectorStoreIndex github.com/jerryjliu/llama_index/issues/1900
Hello Zhijing Eu, Thank you for this great video. Only it is not clear to me how you wired the covariance calculations in the example in the spreadsheet (the table is clear, but where and how is it connected in the model?) Can you please specify what formula's you used and in what lines/cells in the spreadsheet and in the results pagina we can find this? That would be really very helpful. Thank you!
In the tab Uncertain Range+Events+Corr, there is a matrix in cells G14:I16. This is referenced in the risked ranges in cells I4 to I9 as a ",RiskCorrmat" suffix to the whatever risk distribution is being used. Read the help documentation for more examples github.com/pyscripter/XLRisk/wiki/CorrelatedInputsExample
Thank you so much! Really appreciate! 💗 but I have problem, anyone here using Macbook? The RiskPert formula in Excel is not working with the formula shown on the video. Appreciate your comments.
You must be an advanced user I only have Office 365 not 366 🤣. On a more serious note I think XLRisk only works with the excel desktop version (Excel 2010 onwards) but not excel online. github.com/pyscripter/XLRisk
When I open the excel and enable the content all of the formulas become invalid for 'Risked Value' cells. Do I need to link it to the XLrisk file? This is whats in the cell "=@'C:\Users\Lenovo\Desktop\Programming\Excel\XLRisk\XLRisk.xlam'!RiskPert(C4,D4,E4)"
I don't quite understand your question. This tool does not assess the likelihood or impact but assumes you know enough about the phenomenon to select an appropriate probability distribution to simulate it's behavior...you can create two variables- one being a binomial on-off representing likelihood and another variable to reflect the impact range and multiply both distributions to get the overall effect. Is that what you meant ? If you have actual observed data you can even build your own custom distributions. Unfortunately you can't do it in XL Risk but commercial packages like Palisade @Risk or Oracle Crystal Ball have this feature
Not exactly MC simulations but similar concept that uses Geometric Brownian Motion to model share price behavior ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-irMSmRUlIkc.html (Spoiler Alert : It doesn't work as well as you'd think)
(My language is Portuguese) Your article on excel file protection is sensational. I believe it should be easier to protect certain files because it involves a lot of intellectual, creativity and user interest with sometimes very complex solutions. I will study what I can about this, which you exemplified very well. Thanks for sharing. Hugs.
Glad you found the material useful ! Happy this is helping people like yourselves. I wrote this up because it was a real problem i was facing during a particular freelance gig i was on and i couldn't find any material online that covered this topic end to end.
Yeah... complete useless... if you have locked some cells and go to "REVIEW" tab and press "(un)Protect Sheet" button, all locked cells unlock lol ... what a garbage software
