I gochu 🤜🤛

haha, glad I could help!! =)

same story

Glad I could help! You should check out engineer4free.com/project management for all of the PM videos that it did, you might also find them helpful too 🙂

haha, happy I could help!! =) Thanks for watching!

Glad to hear I could help!! You should check out the rest of the PM videos I made here: engineer4free.com/project-management =)

Thanks so much for this comment Marshal, I'm really glad to get this type of feedback =)

I gochu =)

Awesome glad to hear that I’m making sense!! :) :)

Thanks for the comment Cristina! Glad I'm able to help you out =)

Awesome!! You should also check out all the PM vids I did here: engineer4free.com/project-management 😊

Sorry to hear that, I've got a lot of videos on this stuff, you can check out at engineer4free.com/project-management if you haven't already =)

Thanks!! =)

Glad you liked it!!!!!! =)

You're very welcome!!!

Did you find the answer? I am stuck in this question now😢

How did it go!?

Thanks! Glad you liked it 🙂

Thanks for the feedback! Glad I can help 😁😁

You're welcome Jason, glad to hear it =)

You're welcome Eric, thanks for the feedback!!

+MegaMissfitz 😙

Awesome, thanks for the feedback and keep it up!! :)

Love saving lives :)

Your wish came true... Took a while but it came true :)

Hey sorry I don't have anything that covers those. I only have Activity on Arrow (AOA) and Activity on Node (AON) diagrams here: engineer4free.com/project-management

Hey Youcef, you can find all of the hardware and software that I use at engineer4free.com/tools

@@Engineer4Free thx a lot

Good luck bro!

Awesome thanks for the feedback :)

😉

Thanks for commenting! If you haven't already, check out engineer4free.com/PM for the rest of the videos!

The values for ES and EF are all written in tne boxes for each activity. Please rewatch and observe the legend

Hey thanks so much for commenting. You made me realize that I made a video on that already but forgot to add it to the website. It's updated now! See videos #25 and #26 on www.engineer4free.com/project-management

Thanks so much!

You;re welcome, thanks for watching!!

There are two styles of network diagram, one where the activities are the nodes, and one where the activities are the arrows. Check out video #12 here: engineer4free.com/project-management to see a comparison of the two styles.

I'm sorry, I don't understand what you're asking. There are more videos here: engineer4free.com/project-management I recommend watching videos 4 - 9

Glad I could help =)

+Gilmanda S. Atkinson it can really be done either way. Check with your professor which way they do it, and follow that method!

Gilmanda, I think If you start with 1 you’re actually adding a day of calculation. Say 0+1 is 1 day of completion and 1+1 day will give you 2 days completion. Engineer4free is this right? :)

That is beyond the scope of the method in this video where we go FROM a table of dependencies (which inherently includes those two pieces of information) TO a network diagram that then reveals more information about the activities and project. If you are referring to a problem from an academic source then plz clarify/provide some more info and I might be able to help. It might be as simple as your professor asking you to to try to estimate durations and define the relationships based on what makes sense to you, while fitting it all into 15 weeks. If you are dealing with a real project and are lacking information, then consult a professional with project management experience in your industry.

You're very welcome! The full playlist is here: engineer4free.com/project-management =)

Thanks, glad you liked it!

Glad I could help! More videos here: engineer4free.com/project-management =)

You are most welcome! The full playlist is here: engineer4free.com/project-management =)

So the numbers in the network diagram are labels. These labels confusingly represent two times each (except for 0 which only represents one time). It comes from the way Gantt charts are drawn. See this video: www.engineer4free.com/4/how-to-draw-a-gantt-chart 0 represents the beginning of the first day. 1 represents the end of the first day, and the beginning of the second day. 2 represents the end of the second day, and the beginning of the third day, and so on. This is why in the linked video, Activity A has a duration of two days, and it starts on the beginning of the first day (1) and ends on the end of the second day (2), but then Activity B starts on the beginning of the third day (2) and so on. Confusing? yes a bit, but it's just how it's done, and hopefully seeing the Gantt chart helps show why it is. Just remember that these numbers are always labels!! To make things even more confusing, you can decide if you want the beginning of the first day to be a 0, or a 1. So if you depending on which labelling convention you choose, the numbers will always be off by one from the other convention. However, the logic is the same between.. Thanks for watching, and hopefully this helps to make sense of it!

There are two conventions for these diagrams. One starts with a 1 and the other starts with a 0. Each convention is off by one for every value when compared to the other for things like ES, EF, LS, LF, but activity duration, float/slack, project duration will have the same values either way. If you are learning to start with a 0, then just do that. If you are learning to start with a 1, then just do that. The numbers 0,1,2,3,4, etc in the network diagram are just labels that represent points in time. If you start with 0, then 0 marks the beginning of the first day, 1 marks the end of the first day and beginning of the second day. If you start with 1, then 1 marks the beginning of the first day, 2 marks the end of the first day and beginning of second day. And so on. Whether you call the end of the first day 1 or 2, it's still the end of the first day. Does that make sense?

@@Engineer4Free Thank you, yes, I actually learned the CPM through your tutorial very easily, (very clear and concise by the way), but then I got a question wrong because the author of the exam started with 1 which changed the ES day (my answer) as you guessed it, by 1. I'll stick with starting with zero. Thank you.

​@@Engineer4Free Thank you for the clarification. But I have a confusion that if the Early Finish of the activity A and the Early Start of the activity B are same, which means two activities are starting on the same day, which is not possible as per the dependency. Will this not result in less total duration of the project?

Hey, you can find a full list of the software/hardware that I use at www.engineer4free.com/tools

Mani Berenji Totally understand your confusion. If an activity finishes at the end of day 5, the succeeding activity would start at the beginning of day 6. The way I number my networks diagrams is as follows: 0 represents the beginning of day one. 1 represents the end of day one, but also the beginning of day two. So when you see an activity ending on say, "1" that means it ends at 5:00pm on the first day. If a succeeding activity also starts on "1" then that means it is starting at 8:00am on the second day. It seems a bit odd that two different points in time (end of day one and start of day two) have one number to represent them, but image if we had 24 hour work days, then it would be quite obvious that the end of day one and start of day two are marked by the same number. Continuing with this logic, on the network diagram, "2" represents the end of day two and the start of day three. "3" represents the end of day three and the start of day four, and so on. To prove that I'm not crazy, lets look at activities A and B in this video. Activity A is 5 days long, and Activity B is 4 days long. If our "days" start and finish at some arbitrary but defined times (lets say 8am and 5pm, respectively), then activity A will occupy the first 5 full days. The workers performing activity B won't show up at 5pm on Day 5 to start work... they will show up at 8am on Day 6! Then activity B will take 4 full days, and be finished at the end of the 9th day of the project. With that extremely long winded explanation of why 5+4=9, we can actually make sense of the numbering. You can now observe on the network diagram in the video that the beginning of day one of the project was represented with a 0 (not a 1), then the end of day five AND the beginning of day 6 were represented with a 5, and the end of day 9 was represented with a 9. One last thing if I have somehow still managed to keep your attention.... If we were to represent the beginning of day six with a 6, we would have to +4 for the duration of B, and we would have B ending on the end of day ten, which is wrong because 5+4=9 and does not =10. Sorry for such an insanely long explanation, but it all just comes down to the convention that I have used to define points in time using numbers in the network diagram. I highly recommend watching this really short video I made on Gantt charts, because it gives a way more concise and visual explanation of the numbering system: www.engineer4free.com/4/how-to-draw-a-gantt-chart

overlap

Heyo, sorry to report but it's all just hacked together in a drawing program + some video editing tricks. I just draw one boxe template and then copy past them, it's not official PM software. But you can see all the hardware and software that I use here: engineer4free.com/tools and also check the whole PM playlist: engineer4free.com/projectmanagement 🤙

The numbers in the network diagram are labels. These labels confusingly represent two times each (except for 0 which only represents one time). It comes from the way Gantt charts are drawn. See this video: www.engineer4free.com/4/how-to-draw-a-gantt-chart 0 represents the beginning of the first day. 1 represents the end of the first day, and the beginning of the second day. 2 represents the end of the second day, and the beginning of the third day, and so on. This is why in the linked video, Activity A has a duration of two days, and it starts on the beginning of the first day (1) and ends on the end of the second day (2), but then Activity B starts on the beginning of the third day (2) and so on. Hopefully that helps to clarify what's going on!

Thanks Bru. Tell some friends that could use my videos 🙂

🤜🤛

your welcomeeeeeeeee!!

haha, you're welcome Sam! =)

If you are given the table of dependencies, you will generate the ES values yourself. If the project is using basic finish to start relationships like this, then the ES of a successor will be the EF of the predecessor, not the ES.

@@Engineer4Free I am sorry, I came to ask the same question. If A lasts 2 days (monday and tuesday) then its EF is 2. But if B needs to start at the end of A (end of Tuesday), shouldn't its ES be day 3? as in Wednesday morning? So ES=EF+1? Thank you so much!

Found the answers in previous comments, all good thanks :)

@@igorblucke Hoooookai good! I've typed out the answer to that question many times 😅

You're welcome!! 😁

You're welcome Oche!

The same process applies if you have more than one initial activity or more than one terminal activity. If you have more than one initial activity, set ES = 0 for all of them, and add durations of each activity to get EF. If there is a relationship with multiple predecessors, then the same thing applies: select the largest EF of all predecessors as the ES of the successor. If there are multiple terminal activities (just activities with no predecessors) then it's ok if they have different EF's. On the backward pass you would just find the largest EF and set that as the LF of all terminal activities.

Thanks Muhammad! =)

Valid question

Hey, so AFAIK PMBOK starts their numbering with a 1, but I start with a 0. Either way is fine and a valid way of doing project schedules. If you're studying for PMP or similar, then start with a 1. If your in a university class, then start with whatever number your professor likes to use. Now, as to why I start with a 0, it comes from the way I draw my Gantt charts: www.engineer4free.com/4/how-to-draw-a-gantt-chart Plz take a look at that video. I'm into math, so when I draw any type of chart, I like to assign the axis a value of 0. So did my teacher way back when. But the thing you're going to have to wrap your head around regardless of whether you start with a 0 or a 1, is that every value except the axis value represents TWO points in time. If you start with a 0, then 0 represents the beginning of the first day. 1 represents the end of the first day and the beginning of the second day. 2 represents the end of the second day and the beginning of the third day, and so on. This is why in the Gantt chart video that I linked to above, Activity A is two days long, so it ends on the "2" line, but Activity B also starts on the "2" line. This would translate to A having an EF of 2 and B having an ES of 2. If you were starting the whole system with a 1 instead, all the ES, EF, LS, LF values would just be incremented by 1 because of the shift. Hopefully that clears it up, it's a weird thing that gets asked all the time. And to answer your question clearly about the video we're commenting on, because I start with a 0, when Activity A has a duration of 5, it ends at the end of the fifth day, which we represent with a 5 (go look at the Gantt chart video and count five days on it to see the value), B would then start at the beginning of the sixth day, which we also represent with the number 5. So yeah, your right when you talk about the days IRL, but keep in mind these numbers 0, 1, 2, 3, .... are just labels that we give those points in time.

I replied to the OP. Just pinging you incase you don't get a notification that I replied.

Also, you cant start any activity on day 0 ...... doesn't sound real. Activity can only start from day 1, then you have a formula ES + Duration - 1 to have the EF

Activity B can only start the day after (that is 5 + 1, the 6th day)

Welcome =)

Awesome, thanks dude. Glad to hear it!! 👍

You're welcome :) thanks for watching!

You're welcome. You can find the whole playlist at engineer4free.com/project-management too =)

You’re welcome Hasini 🙂

Happy I was able to help you :)

thanks alot

Happy to help =)

You're welcome! Make sure to check out the full playlist here: kzfaq.info/sun/PLOAuB8dR35oeyKU0ojIxD8Muf6Mwc8ugW =)

Hey Anushree, see videos 13-15 here: engineer4free.com/project-management for slack.

No worries! Tell some friends about the site that are in your class :)

These videos are based off of lecture slides from a university course on project scheduling, not a book