Statistical PERT® (SPERT®) is a probabilistic estimation technique that lets anyone create probabilistic estimates for bell-shaped uncertainties – for free!
September 28, 2019 – I’ve updated the Soothsayer templates to Version 1.1. This is a minor update which adds 800 additional tasks to the Soothsayer for Project Contingency spreadsheet, and makes some very minor formatting changes to Soothsayer for Project Risk Analysis spreadsheet. If you’re not familiar with Soothsayer, learn more by reading this whitepaper to discover how using Excel’s binomial distribution functions can help you choose a right-sized schedule and budget contingency for your project.
September 13, 2019 – Pluralsight has published my newest course, Forecasting for Agile Teams. In this course, you will create and share forecasts for your agile software development effort. First, you will learn why forecasting is important. Next, you will discover how to forecast using Microsoft Excel and Statistical PERT, which is available for downloading on this site right here. Finally, you will explore how to improve your forecasts and effectively share them with stakeholders. When you’re finished with this course, you will have the skills and knowledge of agile forecasting so you can forecast future agile-developed products.
September 4, 2019 – The PMI Toronto chapter has announced the details for my October 23 live webinar, “Forecast Your Future World.” Join me for this one-hour, live webinar as I demonstrate how to use the built-in statistical functions inside of Microsoft Excel to create forecasts for your projects and products. PMI Toronto charges a nominal fee ($10) to attend this webinar. You can learn more and register for the webinar here.
July 28, 2019 – This October 23, join me for a live webinar as I present “Forecast Your Future World” on behalf of my host, the PMI Toronto chapter of the Project Management Institute. PMI Toronto is the 2nd largest PMI chapter in the world with a very active membership. This will be a one-hour, non-recorded webinar covering how to create forecasts for agile teams using Statistical PERT. Webinar registration details will be available in the coming weeks.
July 16, 2019 – I wrote and published a new LinkedIn article, entitled “The Küsters Estimation Problem,” which offers a forecasting approach using Statistical PERT Beta Edition Version 2. I wrote my article on the same day that popular LinkedIn “Thought Provoker,” Michael Küsters, wrote this blog article on his personal blog. Michael has great insights on many agile-related topics — highly recommended!
July 13, 2019 – I released a big upgrade to Statistical PERT Beta Edition Version 2! The Version 2 upgrade adds the same data visualization features as what the SPERT Normal Edition has: tri-colored combo charts to show the beta distribution’s bell-curve, plus row-level line Sparklines to show the bell-curve for each row, and an all-new Agile Forecast tab to calculate agile release/delivery dates. There are some minor formatting updates, too. Download the latest Version 2 of Statistical PERT Beta Edition from this site or from GitHub. Also, Statistical PERT Normal Edition bumped up to version 3.0.3 for some very minor format updates.
July 9, 2019 – I released another very minor update to Statistical PERT Normal Edition Version 3. The version 3.0.2 update does a little formatting to some worksheets and replaces the footer link to the GNU GPL webpage so it uses HTTPS instead of HTTP.
July 1, 2019 – I released minor updates to my two Soothsayer™ spreadsheets. Version 1.0.2 simply adds the full text of the GNU General Public License to both Soothsayer for Risk Analysis and Soothsayer for Project Contingency. Also, I created a new GitHub repository for Soothsayer to manage future changes to these spreadsheets. Download the latest version of Soothsayer either from GitHub or navigate to this site’s FREE Downloads page and look for the Soothsayer bonus download links on the right-side of that page.
June 30, 2019 – I released a minor update to Statistical PERT Normal Edition Version 3. The Version 3.0.1 update simply adds the full text of the GNU General Public License (Version 3) and updates the worksheet footers to expressly require that all verbatim and modified copies of Statistical PERT spreadsheets retain the copyright notice, including the author’s name, copyright year, and that the spreadsheet is licensed under the GNU GPL. The forthcoming new Beta Edition Version 2 will contain the same updates when I release SPERT Version 2 later this summer. You can get a sneak peak of Beta Edition Version 2 by visiting GitHub and downloading from the version_2 branch of the spert-beta repository.
June 26, 2019 – I have begun working on Version 2 of Statistical PERT Beta Edition! Version 2 will give the Beta Edition the same data visualization features as Version 3 of Statistical PERT Normal Edition (that is, line Sparklines for each row, plus tri-colored bell-shaped curves for summary combo charts). If you’d like to follow this development and try-out the new features as I add them, you can download Version 2 from GitHub using the version_2 branch of the spert-beta repository.
June 23, 2019 – To increase awareness and public adoption of Statistical PERT, I’ve created two public repositories on GitHub. Using GitHub will provide greater transparency to the ongoing development plans for Statistical PERT. The spert-normal repository will maintain the latest version of Statistical PERT Normal Edition, while the spert-beta repository will maintain the latest version of Statistical PERT Beta Edition.
Moreover, I’ve created two public projects on GitHub, too, which will show anyone who’s interested what my development plans are for enhancing both editions of Statistical PERT. The SPERT Normal Edition Development project will show you future and in-progress enhancements for SPERT Normal Edition, while the SPERT Beta Edition Development project will show you future and in-progress enhancements for SPERT Beta Edition. I haven’t populated these two projects with enhancement ideas just yet, but I will in the weeks to come, especially as I work on Version 2 of Statistical PERT Beta Edition this summer.
If you’d like to participate in the development of Statistical PERT, please contact me!
May 13, 2019 – Last week, Anne Johnson, PMP, from the United States Census Bureau presented at the University of Maryland’s Project Management Symposium 2019. Her presentation, “Capturing Costs & Value of Research Products” included a brief explanation of how the U.S. Census Bureau uses Statistical PERT to estimate project costs. Using Statistical PERT inside their 8-step process, the U.S. Census Bureau has reduced the number of projects that are over-budget by creating better, more reliable cost estimates up-front. Download and read the full whitepaper.
April 29, 2019 – Today I had the privilege of guest lecturing to students enrolled in the same graduate degree program I completed in 2014: the Master of Science in Project Management (MSPM) from The George Washington University’s School of Business. I lectured on how students can easily use Statistical PERT to create task estimates with the same probability of success, which is a necessary pre-condition to use the Unified Scheduling Method, a technique developed by GWU’s own professorship, Dr. Homoyoun Khamooshi and Dr. Denis Cioffi.
March 19, 2019 – Released a minor update to Statistical PERT Beta Edition (Version 1.2). This minor update replaces the link to my old Pluralsight course and points learners to my new course, Easily Estimate Projects and Products. The footer license and no-warranty claim also had minor updates, too. I’ll begin working on the full version upgrade of the Beta Edition in the next couple of months. Beta Edition Version 2 will receive the same data visualization features as what the Normal Edition Version 3 just received.
March 16, 2019 – This week, Pluralsight published a brand-new course, Easily Estimate Projects and Products, which introduces and demonstrates Statistical PERT Normal Edition Version 3. This course offers the most complete way to understand how Statistical PERT works, how to use it to solve practical estimation problems, and how to modify the template to better suit your estimation (forecasting) needs. Watching the course also helps to defray the cost of this website, so I encourage you to watch the course!
March 10, 2019 – Today I released the brand-new, Version 3 of Statistical PERT Normal Edition! Version 3 includes new data visualization features to help see the uncertainty of your estimates. Version 3 includes row-level Sparklines to visualize the uncertainty of a single, 3-point estimate, plus new, tri-colored combo charts to see the uncertainty at an aggregate level. Moreover, Version 3 includes side-by-side comparison of up to three scenarios in the Agile Forecast tab, and Version 3 includes a new, “Super Simple SPERT” tab for easy, beginner-level forecasting. The Beta Edition of Statistical PERT will receive the same data visualization upgrade by late summer 2019.
November 18, 2018 – I released a new, minor upgrade to Statistical PERT Normal Edition. Version 2.4 makes a small change to the Agile Forecast tab so the confidence probability associated with the agile release date better aligns with a Monte Carlo simulation (using SPERT’s “Medium Confidence” in the Most Likely outcome). All Statistical PERT results are routinely compared with Palisade’s @Risk Monte Carlo simulation plugin to assure users of Statistical PERT’s accuracy.
October 26, 2018 – I have struck an agreement with Pluralsight, a leading producer of online training videos for IT and creative professionals, to create a brand-new training course that will replace my now-dated, 2015 course that first introduced people to Statistical PERT. My new, shorter, 2-hour Pluralsight course will be called, Easily Estimate Projects and Products. In this course, I will show how to create estimates and forecasts using the forthcoming Version 3 of Statistical PERT Normal Edition. My new Pluralsight course and the new version of Statistical PERT Normal Edition are both targeted for a January, 2019 release!
October 21, 2018 – In anticipation of new Version 3 of Statistical PERT Normal Edition (January 2019), I updated SPERT® Mobile to a new Version 2a. This is an early-release version. It includes a new cell containing a line Sparkline that shows the implied, bell-shaped, normal distribution curve. Adding Sparklines to SPERT will be part of the new, visual elements that will be part of both editions (Normal and Beta) of Statistical PERT in 2019. Note: You must have Excel® Mobile installed in your smartphone to make use of SPERT Mobile. Download SPERT® Mobile Version 2a now! It’s one of the “Bonus” downloads available on this site.
October 9, 2018 – I’m preparing a new Version 3 of Statistical PERT Normal Edition with an expected release of January, 2019. Version 3 will have new visual features that show the implied, bell-shaped curve for every row with a valid, 3-point estimate. Version 3 will also include a new bar chart showing the bell-shaped, normal distribution curve for the summary row for all 3-point estimates combined. You can download a preview of this new release by going to this site’s Beta Blog and going to that site’s Download page.
October 3, 2018 – I’m heading out to Los Angeles this week for the biggest event of the year for project managers: the PMI Global Conference 2018. I’ll be presenting a team-building and training framework in this presentation: Collabinart: Build Team Collaboration Through Interpretive Art. If you’re attending this event, contact me and let’s meet up!
September 22, 2018 – I’ve published a new, minor release of Statistical PERT Normal Edition (version 2.3) which includes a new, experimental worksheet for creating a release forecast for agile teams based upon story points, user stories or features. Agile forecasting will be a major development emphasis for Statistical PERT in 2019 and beyond. If you use this new worksheet for creating release forecasts for your agile team, please contact me — I’d love to learn how well Statistical PERT satisfies your agile release forecasting needs.
May 1, 2018 – I will be presenting at two upcoming Project Management Institute (PMI) events this year. Locally, I will be presenting “Collabinart” — a collaboration activity using famous, painted artwork — at the PMI South Florida Chapter’s premier event, Professional Development Day, on June 15. Then, this fall, I will present “Collabinart” at the 2018 PMI Global Conference in Los Angeles. The PMI Global Conference runs from October 6 – 8. As these dates draw nearer, I will post more details on my presentation here on this website. If you’re planning to attend either event, be sure to let me know so I can meet and greet you!
March 1, 2018 – I’m beginning a new initiative to adapt Statistical PERT to better fit the needs of agile teams who need to create release forecasts for their products. When I created Statistical PERT in 2014, my goal was (and is) to create simple, free, easy-to-use estimation tools that enable people to make probabilistic estimates for uncertain future outcomes. Read more about this on the Beta Blog and download a development-only build of Statistical PERT geared specifically for the needs of agile teams.
February 20, 2018 – I will present “Stop Predicting, Start Forecasting” at the Palm Beach State College’s Math Awareness Week at the Lake Worth, FL campus. Mathematics and Statistics Awareness Month is a program of the Joint Policy Board for Mathematics (JPBM) – a collaborative effort of the American Mathematical Society, the American Statistical Association, the Mathematical Association of America, and the Society for Industrial and Applied Mathematics. I’ll present to PBSC’s students on Tuesday, April 3, 2018 (time TBD).
August 12, 2017 – To register for my upcoming webinar with PMI-Toronto (“Stop Predicting, Start Forecasting”), visit PMI Toronto’s event page and register. The cost is only $10 for PMI-Toronto members, and $20 for non-members. You can download my UMD whitepaper, “Stop Predicting, Start Forecasting.” The webinar is scheduled for Wednesday, August 23, 2017, from 8P – 9P (EDT).
July 7, 2017 – “Stop Predicting, Start Forecasting” is the webinar presentation I will give on Wednesday, August 23, 2017, from 8P – 9P (EDT) for the Project Management Institute Southern Ontario Chapter (PMI-SOC), which is the second largest PMI chapter in the world, serving more than 5,000 members in the Greater Toronto Area. This presentation was well-received at the PMI South Florida Professional Development Day in May, and at the University of Maryland (UMD) Project Symposium in March. You can download my UMD whitepaper, “Stop Predicting, Start Forecasting.” Webinar details will be released by PMI-SOC in the coming weeks!
June 10, 2017 – “Protect Your Project Schedule Using the Unified Scheduling” is the presentation I will give on Sunday, June 11, 2017, at the AACE International‘s 2017 Annual Meeting. Learn how to Soothsay your project schedule and budget using the Unified Scheduling Method (USM). USM uses the binomial distribution functions of Microsoft Excel to create a right-sized schedule and budget contingency.
May 28, 2017 – “Stop Predicting, Start Forecasting” is the presentation I will give on Friday, June 9, 2017, at South Florida’s premier event for project professionals, the PMI South Florida Chapter‘s Professional Development Day! Learn the difference between predicting and forecasting future uncertainties, and why it’s better to forecast than predict the future. Can’t attend my presentation that day? You can still download my whitepaper that I wrote for the University of Maryland’s 2017 Project Management Symposium: “Stop Predicting, Start Forecasting.”
March 28, 2017 – “Stop Predicting, Start Forecasting” is the presentation I will give on Thursday, May 4, 2017, at the University of Maryland’s 2017 Project Management Symposium in College Park, Maryland. This presentation will explore the difference between predicting and forecasting uncertain, future outcomes. We’ll examine why meteorologists are called “weather forecasters” (not “weather predictors”) and see how project managers can, like meteorologists, better align stakeholder expectations and improve decision-making through forecasting. UMD’s Project Management Symposium is the premier project management event in the Washington DC metro area, and brings presenters and attendees together for a two-day symposium exploring project management topics in five different tracks, including Agile/IT and Integrated Program Management. If you can’t attend this UMD’s Symposium, you can still download and read my Symposium whitepaper, “Stop Predicting, Start Forecasting.”
March 24, 2017 – Read a whitepaper on Soothsayer™. Soothsayer is a freely-licensed, Excel-based, probabilistic, estimation technique for creating a dynamic, right-sized, contingency reserve for either schedule or cost. Use Soothsayer to develop a project contingency for risks when doing risk analysis, or to add a right-sized buffer in a project schedule or budget based upon the reliability of each task duration or cost estimate. AACE® International will publish this whitepaper in its Transactions for the 2017 AACE® International Annual Meeting, held this year in Orlando, Florida. After reading the whitepaper, try downloading and using Soothsayer™ for Project Risk Analysis.
March 1, 2017 – Released Version 1 for Statistical PERT® Beta Edition (and Version 2.2 of Statistical PERT® Normal Edition). The Beta Edition release is the first production release of Statistical PERT that uses Microsoft Excel’s two beta distribution functions, BETA.DIST and BETA.INV. The beta distribution can model a wide range of bell-shaped uncertainties, even if they are severely skewed, making the Beta Edition the most flexible way to model project uncertainties. The new Version 2.2 of the Normal Edition adds a new Beginners tab that makes it even easier to understand and use Statistical PERT. Read the press release that announces Version 1 of Statistical PERT® Beta Edition.
February 8, 2017 – Released Version 2.1 for Statistical PERT® Normal Edition (and Release Candidate 1 of Statistical PERT® Beta Edition). This version includes a new “SPERT® Normal (Mixed entry)” worksheet that allows for manually-entered 3-point estimates plus global and individual heuristics for generating minimum and maximum point-estimates. This offers estimators the greatest amount of flexibility for creating 3-point estimates. Use global heuristics to generate minimum and maximum point-estimates, or override the global heuristic for any row with either manually-entered, minimum and/or maximum values, or select a row-specific percentage adjustment to the Most Likely outcome to create a unique minimum and/or maximum point-estimates.
January 12, 2017 – Released minor version 2.0.2 to Statistical PERT® Normal Edition (and 0.6 Build 3 of Statistical PERT® Beta Edition). Later in 1Q 2017, a new version will include a new “SPERT® Normal (Mixed entry)” worksheet that will allow for both manually-entered 3-point estimates and both global and individual heuristics for generating minimum and maximum point-estimates.
January 6, 2017 – Project Summit / Business Analyst World Conference in Dallas
Learn about Agile Transformation, Risk Analysis, and Statistical PERT at the upcoming Project Summit / Business Analysis World conference coming to Dallas, February 6 and 7, 2017. On Monday, February 6, I will present, ‘Start an Agile Transformation (When You’re Not Sitting in the C-Suite).’ And on Tuesday, February 7, I will present, ‘Protect Your Project by Soothsaying the Risk Register.’ Along the way, I’ll be sharing Statistical PERT with conference attendees, too. Join me – now just one month away!
January 4, 2017 – SPERT® Mobile for Excel® Mobile, Version 1.0.1 Released
SPERT® Mobile is a special adaptation of Statistical PERT for smartphone and tablet users. SPERT® Mobile uses the normal distribution functions of Excel to easily make probabilistic estimates. This specially-sized Excel template displays great on smaller screen sizes. This minor update adds a little better formatting and cell editing.
January 2, 2017 – Statistical PERT® Normal Edition, Version 2 Released
The newest version of Statistical PERT lets you easily make probabilistic estimates using just a single value (most likely) estimate for any uncertainty with bell-shaped risk properties, like: task duration, work effort, expenses, revenue, agile story points, project portfolios, event attendance and more. Improved formatting lets you choose whether to see the left-side or right-side area under the bell-curve. This new version is now branded as the “Normal Edition” of Statistical PERT, indicating that it uses Excel’s two normal distribution functions, NORM.DIST and NORM.INV, and to distinguish it from the Beta Edition. A new development version of the Beta Edition, which uses Excel’s two beta distribution functions, BETA.DIST and BETA.INV, is also available.
December 23, 2016 – What’s New in Version 2, SPERT Comparison with RiskPERT
Want to know what’s new in the upcoming Version 2 release of Statistical PERT – Normal Edition? Check out this blog post. Want to see how Statistical PERT compares with Palisade’s @Risk risk analysis tool? Read this blog post. Statistical PERT – Normal Edition Version 2 and Statistical PERT – Beta Edition Version 0.6 will both be released on Monday, January 2, 2017.
December 19, 2016 – PMBA Conference in Dallas – February 2017
Learn about Agile Transformation, Risk Analysis, and Statistical PERT at the upcoming Project Summit / Business Analysis World conference coming to Dallas, February 6 and 7, 2017. On Monday, February 6, I will present, ‘Start an Agile Transformation (When You’re Not Sitting in the C-Suite).’ And on Tuesday, February 7, I will present, ‘Protect Your Project by Soothsaying the Risk Register.’ Along the way, I’ll be sharing Statistical PERT with conference attendees, too. Join me!
December 12, 2016 – Statistical PERT – Beta Edition Version 0.5 Build 1 released
This is a development build of the next edition of Statistical PERT using the beta distribution. The initial production release of the Statistical PERT – Beta Edition should be available in early 2017. The December build hides columns and makes formatting changes to prepare for the production release next year. Download SPERT-Beta Version 0.5 Build 1 now!
Also, Statistical PERT – Normal Edition, Version 2.0 is announced, and it, too, will be available for downloading in early 2017. Read about all these exciting changes for Statistical PERT here.
November 5, 2016 – Statistical PERT – Beta Edition Version 0.4 Build 2 released
This is a development build of the next edition of Statistical PERT using the beta distribution. The initial production release of the Statistical PERT – Beta Edition should be available in early 2017. The November build adds a pie chart to show the user-specified confidence interval, and the same data validation for the three-point estimate as used in the latest release of the Statistical PERT – Normal Edition. Download SPERT-Beta Version 0.4 Build 2 now!
October 23, 2016 – Statistical PERT is on Twitter!
If you want to keep informed about the latest updates and new releases of Statistical PERT, including the 2017 release of Statistical PERT – Beta Edition, follow this website on Twitter (@statisticalpert). The Statistical PERT website doesn’t require you to share any personal information, register, or create an account before downloading any of the Statistical PERT Excel templates and example workbooks. So, if you want to stay informed about future changes to Statistical PERT, just follow Statistical PERT on Twitter.
October 12, 2016 – Palisade’s 2016 Risk Conference in New Orleans
I’ll be attending Palisade’s biggest risk management event of the year in New Orleans, November 1 & 2. Statistical PERT’s development was greatly helped by comparing its results with Monte Carlo simulations using Palisade’s Excel add-in program, @Risk7. If you’re attending this event, contact me and let’s connect!
October 11, 2016 – New Statistical PERT YouTube channel, 1st video published
Today is launch-day for the Statistical PERT YouTube channel! The first, 16-minute video answers the question, “Why Use Statistical PERT?” Look for more videos soon to learn much more Statistical PERT and how to create probabilistic estimates and forecasts for your projects.
October 10, 2016 – Interview with popular PM blogger, Elizabeth Harrin published
Elizabeth publishes a popular blog entitled, A Girl’s Guide to Project Management. Elizabeth has been blogging about project management topics for many years, and her visually appealing blog is one of the best I’ve seen, as is her content and writing style. Oh, and despite its name, the site is perfectly suited for male project managers, too. 😉
October 7, 2016 – Statistical PERT – Beta Edition Version 0.3 Build 2 released
This is a development build of the next edition of Statistical PERT using the beta distribution. The initial production release of the Statistical PERT – Beta Edition should be available in early 2017. Download SPERT-Beta Version 0.3 Build 2 now!
October 4, 2016 – Version 1.4 Released! This new version makes it easy to create probabilistic confidence intervals for easier range forecasting. And new pie charts show, visually, what uncertainty looks like. Try downloading a template today! Click here to learn more about Version 1.4.
September 20, 2016 – SPERT comes to the 2016 PMI Global Congress – North America! The 2016 PMI Global Congress is less than a week away! Spend part of your conference day learning when, why and how to use Statistical PERT on your projects by attending a 90-minute presentation, Easily Estimate Projects Using Statistical PERT, on Monday, September 26, 2016, from 3:15PM – 4:45PM. Download the PMI whitepaper and presentation here.
September 16, 2016 – Download all SPERT files securely! Starting today, all connections to this site will use Secure Socket Layer (SSL) to encrypt your connection. Whether you’re browsing or downloading, you’ll enjoy the utmost in privacy and confidence when you use the Statistical PERT website!
September 12, 2016 – SPERT™ Mobile is released!
This is special version of Statistical PERT for mobile device users. This simplified SPERT spreadsheet puts the ease and power of Statistical PERT estimation into your hands, wherever you go. The spreadsheet format lets mobile iPhone and Android users easily see and interact with a simple SPERT spreadsheet. To use this special version of Statistical PERT on your smartphone, you must install Excel Mobile on your mobile device. Visit the iTunes store or Google Play to download a free copy of Excel Mobile.
September 10, 2016 – Statistical PERT Version 1.3 for Estimating Tasks is released!
This version offers a new way to specify a confidence interval for all tasks, and see a pie chart of the resulting confidence interval. Also, there is a Quick Start PDF download available to quickly learn how to use and modify any Statistical PERT spreadsheet.
September 5, 2016 – Statistical PERT – Beta Edition Version 0.2 Build 5 released
This is a development build of the next edition of Statistical PERT using the beta distribution. The initial production release of the Statistical PERT – Beta Edition should be available in early 2017. Download SPERT-Beta Version 0.2 Build 5 now!
August 29, 2016 – “Soothsay Your Risk Register” on ProjectManagement.com
August 22, 2016 – “Risk Management Starts Sooner Than You Think” on ProjectManagement.com
July 29, 2016 – Check out my Statistical PERT presentation details at the 2016 PMI Global Congress – North America
June 16, 2016 – The AACE Int’l Annual Meeting is days away! Visit me there to learn about Statistical PERT!
June 4, 2016 – Attend my seminar on Statistical PERT at the 2016 PMI Global Congress – North America!
April 30, 2016 – See Statistical PERT in action at the 2016 AACE Annual Meeting in Toronto this June
February 20, 2016 – See Statistical PERT in action at the 2016 Restoration Industry Association conference
October 26, 2015 – “Evaluating Benefits: Get Statistical (Part 3)” on ProjectManagement.com
October 19, 2015 – “Evaluating Benefits: Get Statistical (Part 2)” on ProjectManagement.com
October 12, 2015 – “Evaluating Benefits: Get Statistical (Part 1)” on ProjectManagement.com
October 6, 2015 – New Statistical PERT template released for annual portfolio planning
October 2, 2015 – Statistical PERT example workbooks and templates are compatible with Excel 2016
September 15, 2015 – “Introducing Statistical PERT” on ProjectManagement.com
September 14, 2015 – Statistical PERT – Beta Edition Announcement
September 9, 2015 – “How Statistical PERT Gives Programmers Confident Estimates” on Pluralsight’s Blog