Analytics for Smarter Software Development

Presented at the Software Experts Summit 2014

Transcript

1. © Microsoft Corporation Analytics for Smarter Software Development Thomas Zimmermann, Microsoft Research, USA Joint work with Chris Bird, Nachi Nagappan and many others.
2. © Microsoft Corporation
3. © Microsoft Corporation 40 percent of major decisions are based not on facts, but on the manager’s gut. Accenture survey among 254 US managers in industry. http://newsroom.accenture.com/article_display.cfm?article_id=4777
4. © Microsoft Corporation analytics is the use of analysis, data, and systematic reasoning to make decisions. Definition by Thomas H. Davenport, Jeanne G. Harris Analytics at Work – Smarter Decisions, Better Results
5. © Microsoft Corporation history of software analytics Tim Menzies, Thomas Zimmermann: Software Analytics: So What? IEEE Software 30(4): 31-37 (2013)
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7. © Microsoft Corporation trinity of software analytics Dongmei Zhang, Shi Han, Yingnong Dang, Jian-Guang Lou, Haidong Zhang, Tao Xie: Software Analytics in Practice. IEEE Software 30(5): 30-37, September/October 2013. MSR Asia Software Analytics group: http://research.microsoft.com/en-us/groups/sa/
8. © Microsoft Corporation guidelines for analytics (1) The Inductive Software Engineering Manifesto: Principles for Industrial Data Mining. Tim Menzies, Christian Bird, Thomas Zimmermann, Wolfram Schulte and Ekrem Kocaganeli. In MALETS 2011: Proceedings International Workshop on Machine Learning Technologies in Software Engineering
9. © Microsoft Corporation guidelines for analytics (2) Be easy to use. People aren't always analysis experts. Be concise. People have little time. Measure many artifacts with many indicators. Identify important/unusual items automatically. Relate activity to features/areas. Focus on past & present over future. Recognize that developers and managers have different needs. Information Needs for Software Development Analytics. Ray Buse, Thomas Zimmermann. ICSE 2012 SEIP Track
10. © Microsoft Corporation © Microsoft Corporation Smart analytics © Microsoft Corporation Development analytics © Microsoft Corporation Usage analytics © Microsoft Corporation The future © Microsoft Corporation What’s next?
11. © Microsoft Corporation Smart analytics
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14. © Microsoft Corporation Jack Bauer
15. © Microsoft Corporation Chloe O’Brian
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17. © Microsoft Corporation All he needed was a paper clip
18. © Microsoft Corporation smart analytics is actionable
19. © Microsoft Corporation smart analytics is real time
20. © Microsoft Corporation smart analytics is diversity
21. © Microsoft Corporation The Stakeholders The Tools The Questions
22. © Microsoft Corporation http://aka.ms/145Questions Andrew Begel, Thomas Zimmermann. Analyze This! 145 Questions for Data Scientists in Software Engineering. To appear ICSE 2014
23. © Microsoft Corporation Microsoft’s Top 10 Questions Essential Essential + Worthwhile How do users typically use my application? 80.0% 99.2% What parts of a software product are most used and/or loved by customers? 72.0% 98.5% How effective are the quality gates we run at checkin? 62.4% 96.6% How can we improve collaboration and sharing between teams? 54.5% 96.4% What are the best key performance indicators (KPIs) for monitoring services? 53.2% 93.6% What is the impact of a code change or requirements change to the project and its tests? 52.1% 94.0% What is the impact of tools on productivity? 50.5% 97.2% How do I avoid reinventing the wheel by sharing and/or searching for code? 50.0% 90.9% What are the common patterns of execution in my application? 48.7% 96.6% How well does test coverage correspond to actual code usage by our customers? 48.7% 92.0%
24. © Microsoft Corporation smart analytics is people
25. © Microsoft Corporation The Decider The Brain The Innovator Photo of MSA 2010 by Daniel M German (dmg@turingmachine.org) The Researcher
26. © Microsoft Corporation smart analytics is sharing
27. © Microsoft Corporation Sharing Insights Sharing Methods Sharing Models Sharing Data
28. © Microsoft Corporation Sharing Insights Sharing Insights Sharing Methods
29. © Microsoft Corporation Branch Analytics Christian Bird, Thomas Zimmermann: Assessing the value of branches with what-if analysis. SIGSOFT FSE 2012: 45 Emad Shihab, Christian Bird, Thomas Zimmermann: The effect of branching strategies on software quality. ESEM 2012: 301-310 Christian Bird, Thomas Zimmermann, Alex Teterev: A theory of branches as goals and virtual teams. CHASE 2011: 53-56
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31. © Microsoft Corporation main Branches at Microsoft
32. © Microsoft Corporation main networking multimedia Branches at Microsoft
33. © Microsoft Corporation main networking multimedia Branches at Microsoft Changes are isolated => Less build and test breaks
34. © Microsoft Corporation main networking multimedia Branches at Microsoft Changes are isolated => Less build and test breaks integration
35. © Microsoft Corporation main networking multimedia Branches at Microsoft Changes are isolated => Less build and test breaks integration integration
36. © Microsoft Corporation main networking multimedia Branches at Microsoft Changes are isolated => Less build and test breaks integration integration
37. © Microsoft Corporation main networking multimedia Branches at Microsoft Changes are isolated => Less build and test breaks Process overhead Time delay integration integration
38. © Microsoft Corporation Code Flow for a Single File Blue nodes are edits to the file Orange nodes are move operations
39. © Microsoft Corporation Branch Decisions How do we coordinate parallel development? How do we structure the branch hierarchy? Can we reduce the complexity of branching?
40. © Microsoft Corporation Branch Analytics Techniques: • Survey developers to understand problems with branching • Mine source control for relationship of teams and branches • Simulate benefits and cost of alternative branch structures Actions/Tools: • Alert stakeholders about possible conflicts • Recommend branch structure (delete, create, fold branches) • Perform semi-automatic branch refactoring
41. © Microsoft Corporation Assessing a Branch Simulate alternate branch structure to assess cost and benefit of individual branches • Cost: Average Delay Increase per Edit How much delay does a branch introduce into development? • Cost: Integrations per Edit on a Branch What is the integration/edit within a branch? • Benefit: Provided Isolation per Edit How many conflicts does a branch prevent per edit?
42. © Microsoft Corporation Simulating Removal of a Single Branch A B integration integration A B A B A Compare 1 with 4 to assess cost and benefit of branch B
43. © Microsoft Corporation Parent Branch Victim Branch Child Branch 65
44. © Microsoft Corporation Parent Branch Victim Branch Child Branch To release branch 66
45. © Microsoft Corporation Parent Branch Victim Branch Child Branch Parent Branch Victim Branch Child Branch 67 Simulation (what-if)
46. © Microsoft Corporation Parent Branch Victim Branch Child Branch faster code flow Parent Branch Victim Branch Child Branch 68 Simulation (what-if)
47. © Microsoft Corporation Parent Branch Victim Branch Child Branch faster code flow unneeded integrations removed Parent Branch Victim Branch Child Branch 69 Simulation (what-if)
48. © Microsoft Corporation Parent Branch Victim Branch Child Branch no longer isolated faster code flow unneeded integrations removed Parent Branch Victim Branch Child Branch no longer isolated no longer isolated no longer isolated no longer isolated 70 Simulation (what-if)
49. © Microsoft Corporation Assessing branches Delay (Cost) Provided Isolation (Benefit) Green dots are branches with high benefit and low cost Red dots are branches with high cost but low benefit Each dot is a branch
50. © Microsoft Corporation Assessing branches Delay (Cost) Provided Isolation (Benefit) Green dots are branches with high benefit and low cost Red dots are branches with high cost but low benefit Each dot is a branch If high-cost-low-benefit had been removed, changes would each have saved 8.9 days of delay and only introduced 0.04 additional conflicts.
51. © Microsoft Corporation Skill in Halo Reach Jeff Huang, Thomas Zimmermann, Nachiappan Nagappan, Charles Harrison, Bruce C. Phillips: Mastering the art of war: how patterns of gameplay influence skill in Halo. CHI 2013: 695-704
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53. How do patterns of play affect players’ skill in Halo Reach? 5 Skill and Other Titles 6 Skill Changes and Retention 7 Mastery and Demographics 8 Predicting Skill 2 Play Intensity 3 Skill after Breaks 4 Skill before Breaks 1 General Statistics
54. The Cohort of Players The mean skill value µ for each player after each Team Slayer match µ ranges between 0 and 10, although 50% fall between 2.5 and 3.5 Initially µ = 3 for each player, stabilizing after a couple dozen matches TrueSkill in Team Slayer We looked at the cohort of players who started in the release week with complete set of gameplay for those players up to 7 months later (over 3 million players) 70 Person Survey about Player Experience
55. 2 Play Intensity Telegraph operators gradually increase typing speed over time
56. 2.1 2.3 2.5 2.7 2.9 3.1 0 10 20 30 40 50 60 70 80 90 100 mu Games Played So Far 2 Play Intensity Median skill typically increases slowly over time Skill
57. 2 Play Intensity (Games per Week) 2.1 2.3 2.5 2.7 2.9 3.1 0 10 20 30 40 50 60 70 80 90 100 mu Games Played So Far 0 - 2 games / week [N=59164] 2 - 4 games / week [N=101448] 4 - 8 games / week [N=226161] 8 - 16 games / week [N=363832] 16 - 32 games / week [N=319579] 32 - 64 games / week [N=420258] 64 - 128 games / week [N=415793] 128 - 256 games / week [N=245725] 256+ games / week [N=115010] Median skill typically increases slowly over time Skill
58. 2 Play Intensity (Games per Week) 2.1 2.3 2.5 2.7 2.9 3.1 0 10 20 30 40 50 60 70 80 90 100 mu Games Played So Far 0 - 2 games / week [N=59164] 2 - 4 games / week [N=101448] 4 - 8 games / week [N=226161] 8 - 16 games / week [N=363832] 16 - 32 games / week [N=319579] 32 - 64 games / week [N=420258] 64 - 128 games / week [N=415793] 128 - 256 games / week [N=245725] 256+ games / week [N=115010] Median skill typically increases slowly over time Skill
59. 2 Play Intensity (Games per Week) 2.1 2.3 2.5 2.7 2.9 3.1 0 10 20 30 40 50 60 70 80 90 100 mu Games Played So Far 0 - 2 games / week [N=59164] 2 - 4 games / week [N=101448] 4 - 8 games / week [N=226161] 8 - 16 games / week [N=363832] 16 - 32 games / week [N=319579] 32 - 64 games / week [N=420258] 64 - 128 games / week [N=415793] 128 - 256 games / week [N=245725] 256+ games / week [N=115010] But players who play more overall eventually surpass those who play 4–8 games per week (not shown in chart) Players who play 4–8 games per week do best Median skill typically increases slowly over time Skill
60. 3 Change in Skill Following a Break “In the most drastic scenario, you can lose up to 80 percent of your fitness level in as few as two weeks [of taking a break]…”
61. -0.03 -0.02 -0.01 0 0.01 0.02 0.03 0 5 10 15 20 25 30 35 40 45 50 Δmu Days of Break Next Game 2 Games Later 3 Games Later 4 Games Later 5 games later 10 games later 3 Change in Skill Following a Break Median skill slightly increases after each game played without breaks Longer breaks correlate with larger skill drops, but not linearly On average, it takes 8–10 games to regain skill lost after 30 day breaks Breaks of 1–2 days correlate in tiny drops in skill Change in Skill
62. Analysis of Skill Data Step 1: Select a population of players. For our Halo study, we selected a cohort of 3.2 million Halo Reach players on Xbox Live who started playing the game in its first week of release. Step 2: If necessary, sample the population of players and ensure that the sample is representative. In our study we used the complete population of players in this cohort, and our dataset had every match played by that population. Step 3: Divide the population into groups and plot the development of the dependent variable over time. For example, when plotting the players’ skill in the charts, we took the median skill at every point along the x-axis for each group in order to reduce the bias that would otherwise occur when using the mean. Step 4: Convert the time series into a symbolic representation to correlate with other factors, for example retention. Repeat steps 1–4 as needed for any other dependent variables of interest.
63. © Microsoft Corporation What’s next?
64. © Microsoft Corporation call to action
65. © Microsoft Corporation Data Analysis Patterns http://dapse.unbox.org/
66. © Microsoft Corporation
67. © Microsoft Corporation Analytics for Smarter Software Development Thomas Zimmermann, Microsoft Research, USA Joint work with Chris Bird, Nachi Nagappan and many others.
68. © Microsoft Corporation Analytics for Smarter Software Development Thomas Zimmermann, Microsoft Research, USA Joint work with Chris Bird, Nachi Nagappan and many others.
69. © Microsoft Corporation Thank you!