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Yuval Yeret

James Shore: Value Velocity: A Better Productivity Metric? - 0 views

  • *Please note that I'm specifically talking about productivity. Velocity is a great tool for estimating and planning and I'm not trying to change that. It's just not a good measure of productivity.
  • rather than asking your business experts to measure business value after delivery (difficult!), have them estimate it beforehand. Every story (or feature--keep reading) gets an estimate before it's scheduled. At the end of each iteration, add up the value estimates for the stories you completed in that iteration. This is your "value velocity."
  • And rather than reflecting the hours programmers work, as cost velocity does, value velocity actually reflects productivity. Remember, productivity equals output/time. Value estimates are a much better indication of output than cost estimates are.
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  • It's like traditional velocity, except it's based on your customers' estimates of value rather than your programmers' estimates of cost.
  • stories don't always have value on their own.
  • Although value velocity isn't perfect, a team with consistent value estimates would be able to graph their value velocity over time and see how their productivity changes. This would allow them to experiment with new techniques ("Let's switch pairs every 90 minutes! Now once a week!") and see how they affect productivity. If balanced with actual measures of value and some sort of defect counting, this could be a powerful tool.
  • just estimate and score features rather than stories.
  • Another option would be to pro-rate each feature's estimate across all of the stories required to deliver it.
  • some types of stories don't provide value in the traditional way. What's the value of fixing a nasty crash bug?
  • Third, value velocity is just as vulnerable to gaming as cost velocity is... perhaps more so. I'm not sure how to prevent this.
Yuval Yeret

Kanban development oversimplified: a simple explanation of how Kanban adds to the ever-... - 0 views

  • It’s a lot easier to estimate a story that’s small — which can lead to more accurate estimates, and better predictability.
  • It’s easier to plan with smaller stories. With big stories — stories that might take weeks for a developer to implement — it becomes difficult to plan a development time-box — particularly when the iterations are only a couple of weeks. It seems that only a couple stories fit — and there’s often room for half a story — but how do you build half a story? Splitting them into smaller stories makes it easier to plan those time-boxes.
  • Shrinking stories forces earlier elaboration and decision-making. Where product owners could write their stories fairly generally and consider many of the details later, now breaking them down into smaller stories forces more thinking earlier in a planning lifecycle.
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  • Managing little stories forces us to keep better track of how they fit together. Product owners are often asked to break down stories to a level where a single story becomes meaningless. To keep track of what’s meaningful to them and other stakeholders, they often need to keep track of bigger items such as the features of the product and how many stories contribute to building up that feature.
  • The result of these herniated time-box activities is a cycle that’s actually 3-4 times longer than our time-box. To get work done, we’ll use a time-box to elaborate stories, one to develop them, another to more thoroughly test them, and if there are bugs, possibly another to fix them.
  • Anyone who’s attended an Agile planning meeting knows they can often last about an hour longer than you can stand it
  • It’s difficult to fit thorough validation of the story into a short time-box as well. So, often testing slips into the time-box after. Which leaves the nasty problem of what to do with bugs� which often get piped into a subsequent time-box.
  • During an ideal Agile time-box we’ll have frequent discussions between developers, testers, and those on a product owner team — like business analysts, user experience people, and business people. We’ll do this to understand what we need to build and describe what we’ll do to validate the story was really done. When time-boxes are short, there’s less time for this conversation. It’s common to move many of the conversations to detail the story and describe acceptance to the time-box before so we can be ready to really get moving with development when the time-box starts.
  • As time-boxes shrink those on the product owner team and testers find themselves in a constant mode of getting ready for a next time-box and evaluating past time-boxes
  • “Kan” means visual, and “ban” means card or board.
  • Kanban cards are used to limit the amount of inventory the factory builds. It doesn’t do the Toyota factory any good to build doors faster then they can assemble cars. It just wastes money on excess doors, and parts of doors. Excess work in progress is considered to be waste in Lean manufacturing. (It’s probably waste in non-Lean manufacturing too.) In the above completely made up example, you’ll never have more than 15 finished doors hanging around. (Mudha is Japanese for waste. Learn it to impress your Lean friends.)
  • work long hours, attend lots of meetings, and seem to have less time to be available to help developers with the current time-box. Since their focus is on a future or past time-box, questions about this time-box seem like interruptions. Collaboration decreases and tensions increase. Their work load is heavy, bumpy, not smooth or even.
  • Kanban thinking in software development attempts to do a similar thing. We want to limit unnecessary work in progress to be no higher than it needs to be to match the throughput of the team.
  • In Kanban development: time-boxed development is out stories are larger and fewer estimation is optional or out completely velocity is replaced by cycle time
  • Exactly what’s left of Agile if we get rid of time-boxes, change the meaning of stories, and stop measuring velocity. And, exactly what do car doors and Kanban cards have to do with software development? Don’t get hung up on process. Remember, agile development isn’t a process.
  • These columns aren’t set. You should discuss with your team the phases that stories go through to be completed. Some organization may use columns for writing documentation, or preparing customer service people to support the feature in production.
  • You might have a column where business analysts spend time tracking down technical details that developers need to understand to write code.
  • The top is used for stories currently in progress in that phase. The bottom is the buffer. When work for that phase of the story is completed, it moves from “in progress” to the “buffer” where it’ll wait to be pulled into the next phase.
  • When we set limits for work in progress, we’ll set a total number for the process step that includes both “in process” and the “finished buffer” for that process step.
  • Stories must be minimal marketable features
  • To be marketable the feature needs to be large enough to be useful — probably larger than the teeny stories that take a couple days to build and seem to be best practice in Agile development today. A MMF may take weeks to build. But the important thing isn’t how long it takes to build, but that it be understandable and valuable to those who’ll receive it. To identify a MMF some folks ask the question “Would I announce it in my company’s product blog?” If it’s too tiny to mention, then it’s not a MMF.
  • To be lean, we’ll limit the number of stories we allow onto the board. A common formula is to add up all the members of the team in all roles and divide by two. All roles includes developers, analysts, user interfaced designers, testers, deployment people — anyone immediately responsible for getting features to market. For example, if team members total 20, we might limit the number of MMF-style stories on the board to 10.
  • Today developers have finished a story, and s they walk to the Kanban board to move it out of development, they notice their single buffer slot is full — and the “testing in progress” column is filled to its limit. What now? The developers talk to the testers. “We’re really struggling to keep up here. It’ll be till tomorrow morning before we can get some of these stories moved out.” “Hmm�” says a developer “Can we help test?” “Of course you can!” says the tester. “With your help we can get these cleared out by the end of the day.“ The tester grins “I just don’t want you validating a story you implemented.”
  • For the limits of the story process steps, the limit is often half the number of people that can perform the work for that phase of development. For instance if you have 6 developers, you might limit the development in progress column to 3. Now, this will force developers to work together on stories. I do find in practice that this may not work out for all teams — so I often see limits that equal the number of developers (or those that can perform the process step) or often 1.5 * the number of people in a role. Of course if you do this, it’ll raise the overall work in progress — and as you might expect, items will take longer to finish.
  • When a column in a Kanban board is full, we know that group is at capacity. We also know that if this keeps happening that that process step is likely where a bottleneck is.
  • If you’ve ever waited in line for the Pirates of the Caribbean in Disneyland you might remember signs along the way that say “Your wait time from here is 30 minutes” — something like that. Now you can post your own wait times on your Kanban board. At the bottom of your story queue post the average cycle time with wait time. It’ll say something like “Your wait time for a story here is approximately 18 days.” At the top of the queue post the average working cycle time. It might say “your wait time from here is 14 days.”
  • But, since there’s no development time-box in Kanban development, we’ll measure story-by-story how long they took to complete — the “cycle time” of the story.
  • When you place focus on how quickly you can get functionality done, and have the ability to measure just that, then the estimates don’t much matter. In fact, many using a Kanban approach have simply stopped estimating at all. Yes story sizes vary, but being able to give a wait time plus or minus a few days is sufficient for many organizations’ concerns.
  • Some do still estimate stories. Then use those estimates in conjunction with cycle time. Using a spreadsheet we can calculate the average cycle time for stories with a given estimate. If you do this, consider placing a handy chart next to your Kanban board showing estimate in one column, and wait times in adjacent columns. With this you’re answering the real question stakeholders are asking for when they get estimates: “when am I going to see this functionality in the software?”
  • The only difference is the cycles aren’t used to plan and commit to stories any longer.
  • If I know that during three week time period there where 15 working days and that 5 developers worked the entire time, that’s 75 developer days. Knowing that lets me calculate the average number of developer days per story: 3.4 (75/22) — Which is darn close to pi — which makes me believe it has to be right. ;-) This number, 3.4, is what XP practitioners referred to as load factor.
  • Evaluation cycles, not development time-boxes
  • If your stakeholders are like mine, they don’t want to know when they’re going to get this functionality, the want to know when they’re going to get all this functionality. I find that if I place stories into a spreadsheet with start and end dates, and calculate cycle time, if I select an arbitrary time period — say a two or three week time period — I can see how many stories where completed during this time period. For instance I might see the team finished 22 stories in 3 weeks — that’s about 7.3 stories per week. Given a backlog of 100 stories I can reasonably infer that it’ll take between 13 and 14 weeks (100/7.3). That’s yesterday’s weather for Kanban — at least the way I calculate it.
  • The daily standup or daily scrum meeting occurs as normal, but now it occurs in front of the Kanban board. Instead of the regular meeting ritual of checking in with each person to find out what they worked on yesterday and will work on today, the discussion revolves around the Kanban board and what will likely move on and off the board today, where “traffic” seems the heaviest, and what we could do to clear bottlenecks.
  • Reflect every few weeks
  • Lean practices help teams increase throughput. They don’t make developers type faster, rather they draw attention to bottlenecks that slow things down, help you see them and respond to them quicker. Using a Kanban board lets you easily visualize work in progress across different roles and lets you see when someone is taking on too much work simultaneously.
  • Demonstrate every few weeks
  • A task board as it’s commonly used in an agile approach can give you the visualization too. But, widening the task board to separate testing from development from acceptance or other process steps helps me better visualize where things are clogging up — helps me better diagnose problems. And, setting hard limits for process steps and respecting them really makes me deal with the problem in a way that dropping a pile of stories into a sprint or iteration didn’t. But, maybe it’s just me who’s lazy and avoids dealing with tough problems. I’m sure you’d never run into a situation where you and your team let lots of finished development work pile up waiting to be tested.
  • There’s no one as zealous as the newly converted There’s a lot of folks pretty excited about Kanban out there. I am too. Sometimes that zeal takes the form of telling people practicing common agile time-boxed development that they’re wrong. But, I guess I’m crusty enough to know that there’s lots of right ways to succeed and anyone who believes they’ve found the best ways is likely wrong. Don’t let those voicing opinions strongly for, or against, Kanban approaches stop you for digging in deeper and understanding the ideas behind it.
  •  
    one of the best articles about Kanban and its relation to Agile I've encountered so far - focusing on Feature development (not maintenance)
Yuval Yeret

James Shore: The Art of Agile Development: Spike Solutions - 0 views

  • About Spikes A spike solution, or spike, is a technical investigation. It's a small experiment to research the answer to a problem. For example, a programmer might not know whether Java throws an exception on arithmetic overflow. A quick ten-minute spike will answer the question.
  • Performing the Experiment The best way to implement a spike is usually to create a small program or test that demonstrates the feature in question. You can read as many books and tutorials as you like, but it's my experience that nothing helps me understand a problem more than writing working code. It's important to work from a practical point of view, not just a theoretical one.
  • Writing code, however, often takes longer than reading a tutorial. Reduce that time by writing small, standalone programs.
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  • Design Spikes Sometimes you'll need to test some approach to your production code. Perhaps you want to see how a design possibility will work in practice, or you need to see how a persistence framework will work on your production code. In this case, go ahead and work on production code. Be sure to check in your latest changes before you start the spike and be careful not to check any of your spike code.
  • If you anticipate the need for a spike when estimating a story, include the time in your story estimate. Sometimes, you won't be able to estimate a story at all until you've done your research; in this case, create a spike story and estimate that instead
Yuval Yeret

Cage Match: Gantt Charts vs. Burndowns : b# - 0 views

  • Lesson #1:  Task-based plans don't convey business value.  Feature-based plans do.
  • Once an estimate proves incorrect, any other estimate based on that one is now incorrect.
  • Lesson 2:  Estimate in size, not duration
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  • Lesson 3:  Actual progress is infinitely more important than planned progress.
  • Lesson 4:  Calculate your velocity and use that to plan for the future.
Yuval Yeret

Thoughts on Estimation - 1 views

  •  
    The Nature of Software Development
Yuval Yeret

No estimates by Vasco Duarte - YouTube - 0 views

Yuval Yeret

Agile Project Management Blog - 0 views

  • Second getting them to understand Story Points, a seemingly meaningless measurement, seemed to be a non-starter for them.
  • deal hours first This is where ideal hours came to the rescue. They were far more able to wrap their heads around ideal hours i.e. if you lock the developers and testers in a room with zero interruptions, how long would it take. I figured that once they got their initial stories estimated in ideal hours down, switching to Story points will be easy as they would have established a scale of reference to compare against. This approach worked really well. They're now into their 3rd Sprint and now that they have an existing scale, whether the number is in ideal hours or story points or dog points for that matter, it really doesn't matter any more. If you're new to agile estimating, and you're having trouble coming to terms with Story Points try this first and then make the switch later.
Yuval Yeret

James Shore: The Art of Agile Development: Stories - 0 views

  • "Non-Functional" Stories AllyPerformance OptimizationPerformance, scalability, and stability—so-called non-functional requirements—should be scheduled with stories too. Be sure that these stories have precise completion criteria. See Performance Optimization for more.
  • Spike Stories AllySpike SolutionsSometimes programmers won't be able to estimate a story because they don't know enough about the technology required to implement the story. In this case, create a story to research that technology. An example of a research story is "Figure out how to estimate 'Send HTML' story". Programmers will often use a spike solution (see Spike Solutions) to research the technology, so these sorts of stories are often called spike stories.
Yuval Yeret

Alistair.Cockburn.us | Agile contracts - 1 views

  • Venture-capital financing model This can be used with any of the above contract forms. In this model, the sponsor gives a round of financing for a certain amount of work, and the contracted company must produce results in order to get more funding. The sponsor can cut their losses at any time if they are not getting the results they need. They can presumably alter the terms of the contract after each work period. The result of a work period need not be working software; it could be a paper study, or a requirements document, or anything the sponsor selects. The venture-capital finance model works well with agile providers, since the agile provider is used to delivering useful, working software early and regularly. I find it an odd irony that the venture capital financiers running start-ups that I have encountered don’t take advantage of their own model to the extent agile teams do. The venture financiers let the evaluation markers occur too far apart in time. If they attached funding to monthly releases, that would oblige the start-up team to think through what it really can accomplish each month. The monthly progress would give the financiers a better sense of the start-up company’s real progress.
  • Venture-capital financing model This can be used with any of the above contract forms. In this model, the sponsor gives a round of financing for a certain amount of work, and the contracted company must produce results in order to get more funding. The sponsor can cut their losses at any time if they are not getting the results they need. They can presumably alter the terms of the contract after each work period. The result of a work period need not be working software; it could be a paper study, or a requirements document, or anything the sponsor selects. The venture-capital finance model works well with agile providers, since the agile provider is used to delivering useful, working software early and regularly. I find it an odd irony that the venture capital financiers running start-ups that I have encountered don’t take advantage of their own model to the extent agile teams do. The venture financiers let the evaluation markers occur too far apart in time. If they attached funding to monthly releases, that would oblige the start-up team to think through what it really can accomplish each month. The monthly progress would give the financiers a better sense of the start-up company’s real progress.
  • Bob Martin’s idea Bob Martin of Object Mentor posted an interesting variant to get around this problem: a base fee per story point, plus a lower-than-usual (close-to or below cost) fee per hour. This biases the contracted company’s to deliver early, but gives them some protection in case work proceeds slower than expected. Bob Martin described it this way:”[A]gree to pay a certain amount for each point completed, plus a certain amount for each hour worked. For example, let’s say you’ve got a project of 1000 points. Let’s also say that a team of four has established an estimated velocity of 50 points per week. This looks like about an 80 man-week job. At $100/hour this would be a $320,000 job. So lets reduce the hourly rate to $30/hour, and ask the customer for $224 per point. This sets up a very interesting dynamic. If the job really does take 80 man-weeks, then it will cost the same. If it takes 100 man-weeks then it will cost $344,000. If it takes 70 man-weeks it will cost $308,000. Notice that this is a small difference for a significant amount of time. Notice also that you, as developer feel strong motivation to be done early, since that increases your true hourly rate.” I have not seen that model in action myself, but several people have written in recommending it.
  • ...2 more annotations...
  • Bob Martin’s idea Bob Martin of Object Mentor posted an interesting variant to get around this problem: a base fee per story point, plus a lower-than-usual (close-to or below cost) fee per hour. This biases the contracted company’s to deliver early, but gives them some protection in case work proceeds slower than expected. Bob Martin described it this way:”[A]gree to pay a certain amount for each point completed, plus a certain amount for each hour worked. For example, let’s say you’ve got a project of 1000 points. Let’s also say that a team of four has established an estimated velocity of 50 points per week. This looks like about an 80 man-week job. At $100/hour this would be a $320,000 job. So lets reduce the hourly rate to $30/hour, and ask the customer for $224 per point. This sets up a very interesting dynamic. If the job really does take 80 man-weeks, then it will cost the same. If it takes 100 man-weeks then it will cost $344,000. If it takes 70 man-weeks it will cost $308,000. Notice that this is a small difference for a significant amount of time. Notice also that you, as developer feel strong motivation to be done early, since that increases your true hourly rate.” I have not seen that model in action myself, but several people have written in recommending it.
  • Norwegian PS 2000 Standard contract http://dataforeningen.no/?module=Articles;action=ArticleFolder.publicOpenFolder;ID=1044 “The main feature of the contract for software development is that it provides mechanisms for establishing a common understanding between customer and the developer and a flexible iterative model for development suited for an environment of uncertainties and risks.” ...” Stage by stage, iterative development model securing ability to benefit from increasing understanding of the requirements and challenges Close co-operation between supplier and customer Incentives and sanctions in combination with target pricing Procedures for conflict resolution with an expert as a mediator ” You need to order it (it costs several thousand Norwegian kronor):
yaelgr

Workshop: Estimation Techniques - 1 views

  • Chihuahua 1 1 1 1 7.5 3 Great Dane 75 80 70 60 75 90 Staffordshire Bull Terrier 16 10 50 25 40 17 Appalachian Mountain Dog 45 60 70 35 30 0 Border Collie 20 20 45 20 35 34 American Cocker Spaniel 15 12 35 30 50 13
Yuval Yeret

http://studios.thoughtworks.com/2007/5/10/continuous-integration-in-the-enterprise-with... - 0 views

  • One of the developers had checked in some code that failed the regression tests. The application, on which the company had spent considerable time, money and effort, was now in an uncertain state. It wasn't behaving as expected. In the past, this type of bug usually wasn't discovered for months. Usually, it wasn't discovered until the System Integration Testing cycle got underway. For this project, that wasn't scheduled for another 6 months.
  • In the past, this bug would have lingered in the code for 6 months before anyone even realized it was a problem
  • . The light had gone off only 6 minutes after the code had been committed. Notice: not 6 months...but 6 minutes!
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  • I told them I just saved them $12,535! They looked around to figure out how. The reason I was there was simple. Earlier that year, those same IT managers had performed a series of calculations to estimate how much it cost the department each time a bug made its way out of development, into SIT, into User Acceptance Testing, or all the way into production. For this IT shop, one bug into SIT cost them $12,605 (and you can imagine how much a bug into production would cost.)
Yuval Yeret

InfoQ: What is Velocity Good For? - 2 views

  • Doubling velocity (story points done-done in each sprint) usually means we must improve several things:
  • a clearer definition of done
  • no [known] bugs escape the Sprint
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  • we must prioritize the impediments, and keep removing or reducing the top one until velocity is doubled
  • Hint: We might want to prioritize the impediments by how much the removal/reduction will increase velocity. 25% here, 30% there; pretty soon you're talking a real increase in velocity.
  • Hint: Improving quality and reducing technical debt are almost always important keys to seriously increased velocity. Not the only keys, but very important.
  • Velocity is best used for long term planning. I can look at my velocity over several iterations and come up with an average (Preferably a range.) Then I can use that information to say things like: 1) Given the current backlog, how many iterations is it likely to take to complete a given set of stories? 2) How many story points, and by extension what set of prioritized stories, can I deliver by date X (e.g. in time for the trade show?)
  • I am very wary of anyone who suggests increasing velocity is a goal. *They are just estimates*. It is so easy to game. I've seen it happen both consciously and subconsciously with very undesirable effects.
  • The only measure of increased productivity is completed work. Measuring this also has the desirable side effect of encouraging people to break work down into the smallest possible deliverable units.
Yuval Yeret

Do It Yourself Agile: Scrum and Kanban - Like Chocolate and Peanutbutter - 0 views

  • When doing Kanban, you still need to do the equivalent of planning, assignment, estimation, retrospectives, delivery, etc. In Kanban, all of these activities are decoupled from each other whereas in Scrum they are all coupled to the iteration boundary. How can this be applied to Scrum? Consider retrospectives. If you are just starting with Scrum, you probably have an iteration length of 1 month (or four weeks). From that it follows that you will have a retrospective once per month. If you eventually end up with an iteration length of 1 week, then it follows that you will have a retrospective every week. But this actually seems like the wrong way to set the cadence of retrospectives. Wouldn’t it be better to have the cadence of retrospectives meet the need for them? If it eventually makes sense to do a retrospective every week, doesn’t it make sense to get the benefit of them on a weekly basis when you are just starting Scrum?
Yuval Yeret

Agile Product Manager in the Enterprise (5): Responsibility 3 - Maintain the ... - 0 views

  • The Roadmap consists of a series of planned release dates, each of which has a theme and a prioritized feature set.
  • While it is a simple thing mechanically to represent the Roadmap, figuring out the content for anything beyond the next release is another matter entirely. The topic of what else the team plans to ship and when can be a fascinating and contentious topic in agile
  • the easiest way to think about the Roadmap is that it is an output, rather than an input to the Release Planning process.
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  • The dates and themes for the next release are fixed. The features are prioritized and variable.
  • The teams can commit only to the features in the next upcoming release. Releases beyond the next, represent only a best estimate.
  • The Roadmap, then, is a “plan of intent” and is subject to change as development facts, business context and customer needs change. With respect to the upcoming release, perhaps the most important guidance is this:
  • Even though the team has committed to the objectives and we have agreed that the feature set cannot be guaranteed, it is a reasonable expectation that the agile teams will: 1) meet the date 2) accomplish the theme 3) deliver most of the features, and certainly the highest priority ones, with the requisite quality.
  • Anything less would be unprofessional and belie the power, discipline and accountability of our agile enterprise model. Moreover, it will eventually threaten our own empowerment, as failure to deliver will inevitably cause the implementation of various controls to “help us”!
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