Asked by: Alejandrino Cintrano
business and finance executive leadership and management

What are the differences between bottom up and top down estimating approaches?

Last Updated: 3rd May, 2020

In the top-down approach youwillestimate the duration of deliverables and/ormajordeliverables. In bottom-up estimating youprovidedetailed estimates for each individual task makingupyour deliverables. Generally, top-downestimating isdone first and then later followed upwithbottom-up estimating.

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Then, what is the difference between top down and bottom up approach?

Difference between Top-downandBottom-up Approach. The algorithms are designedusingtwo approaches that are the top-downandbottom-up approach. In thetop-downapproach, the complex module is divided intosubmodules. On theother hand, bottom-up approachbegins with elementarymodules and then combine themfurther.

Secondly, what is a bottom up estimate? Bottom-up estimating is aprojectmanagement technique in which the people who are going to dothework take part in the estimating process. Settingtheestimates of the amount of work, duration and cost at thetasklevel lets you combine them into estimates ofhigher-leveldeliverables and the project as a whole.

Consequently, what is top down and bottom up estimating?

Top Down estimating is a projectestimatingtechnique whereby the overall project isestimated first, andindividual tasks are apportioned from it.Top Down is theopposite of Bottom Up Estimating,whereby individual tasksare estimated first and “rolledup” into theoverall projectestimate.

Which type of cost estimating is the preferred most accurate method?

Three-point Estimation The three estimates are the mostlikelycost, the pessimistic cost, and theoptimisticcost. It reduces bias, risk, and uncertainty fromtheestimation. It is more accurate than theanalogousand parametric estimating techniques. This is themostaccurate technique of all themethodspresented.

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Dimitry Henzl


How Oops is bottom up approach?

Whereas object oriented programming languageslikeC++ and Java programming language follows bottom upapproach.Top down approach begins with high leveldesign and ends withlow level design or development. Whereas,bottom up approachbegins with low level design ordevelopment and ends with high leveldesign.

Jasmina Zieschang


What are the advantages of top down approach?

The advantage of this approach isthatdecisions can be made and implemented very quickly. Thisisparticularly important when time is limited. The other benefitoftop-down project planning is that it helps aligntheproject goals with the organization's strategic goals asuppermanagement is giving the directions.

Welington Yvelain


Is recursion top down or bottom up?

Going bottom-up is a way toavoidrecursion, saving the memory cost thatrecursionincurs when it builds up the call stack. Putsimply, abottom-up algorithm "starts from thebeginning,"while a recursive algorithm often "starts fromthe end andworks backwards."

Lexie Rizquez


What does it mean to be top down?

used to refer to a situation in which decisions aremadeby a few people in authority rather than by the people whoareaffected by the decisions: atop-downapproach/strategy. Opposite.bottom-up.

Daria Kampfle


How do you use top down approach?

Using theTop-DownApproach
The top-down approach to definingprojecttasks involves starting with the project goal or finaldeliverableand breaking it down into smallerplanningchunks.

Urko Kirchenmaier


What is bottom up approach in community development?

Bottom-up approaches emphasisetheparticipation of the local community indevelopmentinitiatives so that they can select their owngoals and the meansof achieving them. On the other hand top-downapproaches areconsidered as development planned byexperts at the top, whoalso lead the process.

Friedhelm Galazo


What is a bottom up strategy?

The bottom-up approach is the oppositeoftop-down investing, which is a strategy that firstconsidersmacroeconomic factors when making an investmentdecision.Conversely, making sound decisions based onabottom-up investing strategy entails pickingacompany and giving it a thorough review priortoinvesting.

Ramzan Kopple


What is the bottom up approach in psychology?

The bottom-up approach tooffenderprofiling is sometimes known as the Britishapproach, and isa data-driven approach that makes useof statistical data onsimilar crimes that have been committed, inorder to makepredictions about the characteristics of anoffender.

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How do you create a bottom up budget?

The following is the basic process that organizationsfollowwhen formulating a bottom-up budget:
  1. Identify the individual components of the business.
  2. Get a sum of cost projections of each department.
  3. Sum up the budgets of all departments.
  4. Submit for approval.

Soulaimane Labeaundi


What is bottom up approach in project management?

Top down strategy involves themanagementof a project, i.e. the projectmanager havingcomplete control over the delegation of tasks andthe setting ofthe project schedule and deadlines. On theother hand, thebottom up approach calls for more input fromthose who willbe completing the tasks.

Rauda Quintilla


What is 3 point estimation technique?

Three-point estimation. From Wikipedia, thefreeencyclopedia. The three-point estimationtechnique isused in management and information systemsapplications for theconstruction of an approximate probabilitydistributionrepresenting the outcome of future events, based onvery limitedinformation.

Hademou Aspa


Why use bottom up estimating?

Bottom-up Estimating[Technique]Bottom-up estimating is an extremelyhelpfultechnique in project management as it allows for the abilityto geta more refined estimate of a particular component ofwork.In bottom-up estimating, each task is brokendowninto smaller components.

Makhtar Otaegi


What do you mean by Critical Path?

In project management, a critical path isthesequence of project network activities which add up to thelongestoverall duration, regardless if that longest duration hasfloat ornot. This determines the shortest time possible to completetheproject.

Tadas Miedes


What is analogous estimating?

Analogous estimating is a techniqueforestimating a variety of project parameters and measuresofscale. It is frequently used to estimate the size ofaparticular parameter when information as to thatparticularparameter within the current project is limited orunavailableuntil a later date.

Jiandong Romero Hombrebueno


What is comparative estimating?

Comparative estimating (analogous)
Comparative estimating involves comparingcurrentor completed tasks or projects for which you have somemeasures oftime and resources required. This method is based onpast experiencerather than opinion, but it is only useful if theanalogy isvalid.

Romaysae Ciriano


What is definitive estimate?

The definitive estimate is the mostaccurateestimate for the amount of work and resources neededtocomplete the project. They are estimates consider to havea"+ or – 20%" accuracy.

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What is parametric estimating?

Parametric estimating, a more accuratetechniquefor estimating cost and duration, uses therelationshipbetween variables to calculate the cost orduration.Essentially, a parametric estimate is determinedbyidentifying the unit cost or duration and the number ofunitsrequired for the project or activity.

Tawny Geerlings


What is top down management?

Top-down management occurs whengoals,projects, and tasks are determined among your organization'sseniorleaders, usually independently of their teams. Thesegoals,projects, and tasks are then communicated to their teams.Pros:Top-down management is the most common approachtoorganizational management.

Zaid Pandele


What are the methods of estimation?

5 Successful Methods of Project Estimation
  • Expert judgment. This is probably the most common way peoplegeta project estimation.
  • Comparative or analogous estimation. If your current projectissimilar to past ones, take the data from previous workandextrapolate it to provide your estimates for the new job.
  • Top-down.
  • Bottom-up.
  • Parametric model estimating.