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@Sherlock_Ohms 11 күн бұрын
Hi Tallys, I was wondering if you could tell me why when you increase the initial amount to say, $100,000, the solver then says that the problem is no longer linear?
@TallysYunes 11 күн бұрын
Assuming it was solving before (with 50,000) as the initial amount and not complaining of non-linearity, simply changing the initial 50K to 100K should not be generating this issue. Therefore, it's some sort of bug. I've seen these before with Solver. Sometimes, clicking (or un-clicking) the box that says "Automatic scaling" in the Solver options takes care of this.
@Sherlock_Ohms 11 күн бұрын
@@TallysYunes Thanks! I suppose another way around it would be to convert the initial amount to thousands of dollars, so 100 in my case. This solves fine.
@TallysYunes 11 күн бұрын
Yes, indeed. Sometimes if you scale the numbers yourself so that the difference between the smallest and the largest number in the data is reduced, this kind of bug goes away. Good thinking!
@robertosei-danso5729 Ай бұрын
How do you formulate this with two plants?
@TallysYunes Ай бұрын
If by "two plants" you mean two different products whose inventories have to be tracked, you can simply duplicate the variables and repeat the same set of constraints for each product individually.
@robertosei-danso5729 Ай бұрын
@@TallysYunes It's more transshipment in my case. Solver cannot find a solution.
@TallysYunes Ай бұрын
Check out the transshipment example on my playlist (if you haven't yet) and double check that all your constraint formulas are correct. If it can't find a solution, there's at least one constraint that is being too strict.
@morning0628 Ай бұрын
Anyone who got 6.333333 for X1 instead of 1.333333?
@TallysYunes Ай бұрын
This problem has alternative optimal solutions. As long as you still get 22.333 in cell H16 and all the constraints are satisfied, you're fine.
@morning0628 Ай бұрын
@@TallysYunes thank you!
@xwz6957 Ай бұрын
if my solver could not find a feasible solution, where and how can i find my own mistake?
@TallysYunes Ай бұрын
This is caused by the problem being over constrained and the issue is with one of the (or a group of the) constraints. What I usually do is this: go to the grey area (i.e. the variables), start with it empty, and then assign some simple values to the grey cells (for example 1 or 2) and check that the resulting calculations that use those cells are returning the values you'd expect to see. Or try inputting a solution that you know should be feasible and then see if some calculated number looks weird. For instance, in this problem, type in the gray area a solution that only makes one type of gasoline. Try this with all gasolines (one at a time). You'll eventually find out where the issue is. In the worst case, go back to the beginning of the video and double check that all the formulas you are typing match mine exactly. Good luck!
@roberthuff3122 Ай бұрын
🎯 Key Takeaways for quick navigation: 00:00 *📚 Introduction to Integer Programming in Excel* - Overview of transitioning from linear to integer programming, focusing on integral or whole number variables and binary variables for decision-making. - Introduction to binary variables for yes/no decisions and their common applications. - Preview of utilizing binary and whole number variables in Excel models. 02:08 *🎯 Budget Allocation Problem: The Knapsack Problem* - Explanation of the budget allocation problem as a practical application of integer programming, referring to the historical knapsack problem. - Setting the scenario for applying a budget allocation strategy using binary variables in advertising channel selections. - Detailing the process of mapping out the problem's constraints and objectives using a hypothetical business case. 06:05 *💻 Setting up the Excel Model for Integer Programming* - Instructions on creating the Excel model for the problem, including data input, defining binary variables, and formulating the objective and constraints. - Demonstrating the setup of formulas for total exposure and total expense based on binary decisions. - Guidance on using Excel Solver for maximizing exposure within the budget constraint by adjusting Solver parameters for binary variables. 11:07 *🔄 Different Applications of the Knapsack Problem* - Describing the versatility of the knapsack problem by illustrating various real-life applications beyond budget allocation, such as camping gear selection and space mission preparation. - Highlighting the adaptability of the problem structure to different contexts, including time management, space utilization, and auditing projects. - Introduction to extending the binary variable model to accommodate logical conditions in subsequent scenarios. Made with HARPA AI
@vijayrao6321 Ай бұрын
This is fantastic, Professor! I'd like your thoughts and advice on how to do an MCSim with triangular distribution where the lower bound is negative? Thanks in advance!
@TallysYunes Ай бұрын
What are the 3 parameters of this triangular distribution?
@vijayrao6321 Ай бұрын
Essentially I’m trying to model future growth in an industrial company that has historically (15 years data) varied from -2% to +8% with median at 3%.
@TallysYunes Ай бұрын
If the triangular function doesn't allow you to enter a negative for the low end, you can shift everything up 2% points and subtract afterward. For example: Cell A = randtriangular(0, 0.05, 0.1), and B = A - 0.02. This will make cell B behave as if it were a randtriangular(-0.02, 0.03, 0.08).
@vijayrao6321 Ай бұрын
@@TallysYunes Thanks, Prof! Will try this.🙏
@suryaramesh152 2 ай бұрын
So good ! Thank you so much
@TallysYunes 2 ай бұрын
You're welcome!
@JohnFerrante-ep3jw 2 ай бұрын
dude! I just enrolled in a mba and they have me doing linear optimization. The initial problems weren't bad, but it just seriously kicked up a notch. Would really appreciate if I could send you this one problem in particular and see how you would approach it.
@TallysYunes 2 ай бұрын
I can't do homework for you, but it's likely that the one you need to tackle is similar to one of the examples in my videos. Look through my Excel Models playlist.
@JohnFerrante-ep3jw 2 ай бұрын
@@TallysYunes of course not! I'll be sure to check out the videos. I'm struggling with determining if it's blending or allocation, and determining the inequalities for blending. Especially when there's multiple rates and units of measurement. Do you offer tutoring?
@TallysYunes 2 ай бұрын
At the moment I don't have time for one-on-one tutoring, but this is something your teacher would be able to clarify for you (it's their job). Have you tried reaching out to them? Do they offer office hours?
@Sherlock_Ohms 2 ай бұрын
Professor Yunes, Not sure if you still read these but I am loving these videos which help me in my job. My question is, could you force the variable cells to be integers?
@TallysYunes 2 ай бұрын
Thank you! I'm glad the videos are helping. Yes, you can add an "int" constraint on the gray cells. I don't do it in this video because I use this example to illustrate the ideas I go over at the end of the video to my students.
@Sherlock_Ohms 2 ай бұрын
@@TallysYunes Can I ask what book you recommend? I see a few popular recommendations online. What would you choose?
@TallysYunes 2 ай бұрын
Here's one that I like: www.amazon.com/Spreadsheet-Modeling-Decision-Analysis-Introduction/dp/130594741X
@mihaelazeger5705 2 ай бұрын
Hi sir, Can you tell me which video to watch to know how to model this problem in excel so I can solve it and follow through this video? Thanks in advance!
@TallysYunes 2 ай бұрын
I don't have a detailed video on that, but at the beginning of this video I show you the mathematical formulation and the setup of the Solver window (you can pause the video at that moment and look at what I did). The formulas in column F and in cell B12 are all the same: a SUMPRODUCT. If you watch and understand the Farmer Problem example I have on this channel, you should be able to do this one.
@user-op4wr4kp9w 3 ай бұрын
Good video, Thank you!
@matlholelosaba4977 3 ай бұрын
Recorded four years ago and still relevant and so helpful. I wonder how this will change with new developments in Excel and the use of AI.
@rg73140 3 ай бұрын
Hi I would like to check, if the constraint is this instead, what would the equation be? If we advertise on channel 3, we must also advertise on channel 9 and 10,
@TallysYunes 3 ай бұрын
In this case, you can deal with it as if it were two separate statements and it will result in two constraints: a) If we advertise on 3, we must also advertise on 9. b) if we advertise on 3, we must also advertise on 10. You can do each of the above with the "if this then that" formula that the video teaches.
@domfernandez98 3 ай бұрын
wasted hours yesterday checking whether my input variables were correct... Thank you so much for the help!
@TallysYunes 3 ай бұрын
You're welcome!
@user-eh6yl2ej5m 3 ай бұрын
You are a very excellent teacher, thank you very much
@TallysYunes 3 ай бұрын
Thank you!
@koji.o 3 ай бұрын
Subscribed! I hope there's also a version using purely excel formulas, without using 3rd party paid programs such as 'Simvoi'
@TallysYunes 3 ай бұрын
Thank you! There may be, but I'm not aware of any native Monte Carlo facilities for Excel other than the brute force way that can become very time consuming.
@tbirdspy8911 4 ай бұрын
This was a huge help completing my homework assignment in time. Thank you!
@TallysYunes 4 ай бұрын
You're welcome!
@abdulganiyuosman3026 4 ай бұрын
I undoubtably enjoyed your video. I subscribed right away.
@TallysYunes 4 ай бұрын
Awesome! Thank you!
@PalakpreetKaur-jb8mw 4 ай бұрын
🙌🏻🤌🏻
@user-fk5sc1dy2d 5 ай бұрын
such a great man, you saved our life
@TallysYunes 5 ай бұрын
You're welcome.
@lydiekrickel6093 5 ай бұрын
Very well explained to be able to interpret these tables !
@TallysYunes 5 ай бұрын
Thank you! I'm happy to hear it helped!
@user-jp9iw7kq9m 5 ай бұрын
Note that the you will get 74,908.9 as initial amount for target 100K if the inflows/outflows are baked in. Without inflows/outflows, you should get 71,179.44 as the initial amount needed.
@user-jp9iw7kq9m 5 ай бұрын
Great Video, you deserve more subs. Keep it up!!
@user-jp9iw7kq9m 5 ай бұрын
I meant great playlist, not just this video. Doing a marathon of the playlist now :)
@romeokodi9868 5 ай бұрын
You are great man thanks a lot
@TallysYunes 5 ай бұрын
Thank you! And you're welcome. I'm happy to hear the video was helpful.
@vusiarmstrongmalinga6676 6 ай бұрын
Thank you for the clear tutorial. Manage to understand this clearly now.
@TallysYunes 6 ай бұрын
Great to hear!
@swaritagarwal6387 6 ай бұрын
Amazing! Really helpful
@TallysYunes 6 ай бұрын
Thank you!
@kif2770 6 ай бұрын
Great explanation. Thank you!
@TallysYunes 6 ай бұрын
You're welcome!
@usmanmuhammad3439 6 ай бұрын
Thank you Prof. for given us all these great knowledge for free.
@TallysYunes 6 ай бұрын
My pleasure!
@bdobin8 6 ай бұрын
thank you , really helped out
@TallysYunes 6 ай бұрын
You're welcome! Glad it helped!
@piyushsharma9382 6 ай бұрын
Professor, your passion for the subject is amazing. Would love to learn more things from you
@TallysYunes 6 ай бұрын
Thank you so much!
@anggunamalia753 7 ай бұрын
Terimakasih banyak bapak
@TallysYunes 7 ай бұрын
You're welcome!
@Juan82777 7 ай бұрын
Brilliant
@machkouratibrahim7949 7 ай бұрын
Where do we add Long-term debt on DCF Analysis ?
@TallysYunes 7 ай бұрын
I'm not a finance person, so I'm going to need you to give me a thorough explanation of what you're trying to do exactly. Beginning with the definitions of "long-term debt" and "DCF Analysis." Haha!
@tomdapchai 8 ай бұрын
thanks prof
@sumayaabdulrahman471 8 ай бұрын
Thank you so much for explaining, based on your previous video in the playlist i was thinking if we have an additional constraint that if i select the neighbourhood (x) then the adjacent neighbours to x cannot be selected, so then I'll have to place fire stations in neighbourhood such the neighbourhoods that are adjacent to it are not selected, so how can i add this constraint here as a mathematical formulation ?
@TallysYunes 8 ай бұрын
If I understand your question correctly, you replace the symbol >= with = so that exactly 1 neighborhood is chosen and all the other adjacent ones can't be chosen.
@sumayaabdulrahman471 8 ай бұрын
@@TallysYunes oh Thank you, if change the equality sign from>= to = it is not providing any solution to me :(
@sumayaabdulrahman471 8 ай бұрын
for example, one of the solutions can be neighbourhoods 1,8,6 as these are not adjacent neighbourhoods and at the same tile 1,8,6 cover all their adjacent neighbourhoods too, that is basically what my question is to choose neighbourhoods to place fire station that are not adjacent to each other but at the same time cover all neighbourhoods too, i hope you understand my question
@TallysYunes 8 ай бұрын
Ah, OK. NOW I understand what you were asking. Then bring all the original constraints back to >= 1 and, for every pair of neighborhoods that are adjacent, add a new constraint saying at most one of them can be = 1. So for example, because 1 and 2 are adjacent, you add the constraint x1 + x2 <= 1. Repeat for every pair of adjacent neighborhoods. There will be lots of these.
@ciai7317 8 ай бұрын
Yunes would you have any problem solution related to quantity production, maximizing profit, with constrains of machine hours and man hours, but simultaneously with information about the manufacture operation a specific hours per week. I got confuse, when for instance, I'm given: man hours, numbers of machine, machine hours, number of hours available for all machines, but at the same time the problem a number of operation hours per week of the plant. Help please.
@TallysYunes 8 ай бұрын
Think about each kind of resource separately. A product can consume a certain amount of man hours and a certain amount of machine hours. So your constraints could be: (man hours consumed) <= (man hours available) (machine hours consumed) <= (machine hours available) The latter constraint could be one per week (if your variables are products produced per week) or a single one for the entire operation. Without seeing more details of the problem, it's hard to tell. At the moment, I don't have a specific video of an example that's similar to what you describe. But this is a good idea for a future video.
@sumayaabdulrahman471 8 ай бұрын
This is amazing wow!!!!!!!! not me going back and watching the episode again to view with an optimization eye angle :))). keep posting such amazing creative content. THANK YOU
@TallysYunes 8 ай бұрын
Haha! Thank you! I'm happy to hear you enjoyed it! I'm on season 6 now but haven't found another case yet where optimization could help. But this was a fun video to make.
@sumayaabdulrahman471 8 ай бұрын
Yes ofcourse! also i wanted to ask if you do not mind all the questions that you cover in the playlist are covered by my optimization professor so was wondering what textbook or reference do you use to get these questions so that i can practice more with similar questions?@@TallysYunes
@TallysYunes 8 ай бұрын
The videos in my "Excel Models" playlist go over the examples I cover in my intro to optimization class that I teach at the Undergrad/Masters/MBA level. I followed the book by Cliff Ragsdale entitled "Spreadsheet Modeling and Decision Analysis" until 2019 (been using my own notes since then). If you're looking for additional practice problems on these topics, this book is a great source of examples. You can get a used 7th edition of this book on Amazon for very little money.
@ethanfretag7616 8 ай бұрын
would be nice if you could get to the point of the video!
@TallysYunes 8 ай бұрын
🤣 The point of the video is explained within the first 2 minutes. 🤣
@jaiso434 9 ай бұрын
definitely the best explanation i have found.
@TallysYunes 9 ай бұрын
Thank you! I'm happy to hear the video has been helpful.
@shubhamkumarsingh21 9 ай бұрын
best explanation of the sensi report.
@TallysYunes 9 ай бұрын
Thank you!
@wolfbrr 9 ай бұрын
lovely, my brain blew off yesterday while doing the assignment...thank you.
@TallysYunes 9 ай бұрын
You're welcome!
@mangkuk 5 ай бұрын
same
@Erik_The_Viking 9 ай бұрын
This is a cool problem! Perfect for showing binary integer programming models.
@TallysYunes 9 ай бұрын
I agree! Glad you liked it!
@andersdupontchristensen9039 10 ай бұрын
Thanks man it helped a lot :D
@TallysYunes 10 ай бұрын
You're welcome!
@NykMadison 10 ай бұрын
Thank you so much for this Video Not even in your class but really helped me
@TallysYunes 10 ай бұрын
You're very welcome!
@daniellebenjamin2971 10 ай бұрын
Really cool. I'm trying to solve a problem with multiple constraints... I'm spinning my wheels!
@TallysYunes 10 ай бұрын
Take a look at my "Excel Models" playlist. There's a good chance the one you're trying to solve is similar to a problem I address in there.
@marliesilva 10 ай бұрын
very nice videos
@TallysYunes 10 ай бұрын
Thank you!
@user-wh4ke3rd5u 9 ай бұрын
@@TallysYunes Can you videos about: MILP to solve Job Shoo scheduling problem using excel. Like this one: www.ijmer.com/papers/Vol7_issue3/Version-2/D7322329.pdf I really hope you can do 👌🙏
@aaromalajikumar4340 10 ай бұрын
if a problem include production cost in plant how to include those in to the cost equation
@TallysYunes 10 ай бұрын
If these are costs per unit produced (rather than fixed costs), they can be added to the costs of the arcs that depart from the plant.
@user-wh4ke3rd5u 8 ай бұрын
Hello Sir, please make a video about this: drive.google.com/file/d/1QLdiRT3rzqgYntI6sJy5SOmhFCqUaTWf/view?usp=sharing but using Excel not Lingo! @@TallysYunes
@user-wh4ke3rd5u 8 ай бұрын
I hope you can do that sir🙏
@angelcrmmlozanoiturria3975 10 ай бұрын
WoW!!