helping end-user programmers share their creations (literature review)

Helping End-User ProgrammersHelping End-User ProgrammersShare Their CreationsShare Their Creations

(literature review)(literature review)

Christopher Scaffidi

Carnegie Mellon University

ISR Software Research Seminar 4/16/07

22

Kids “share” creations on the fridge.Kids “share” creations on the fridge.

Of course, other kids better not mess with posted pictures!

This is “read-only” “sharing”... different from “sharing code”!

Introduction

33

End-user programmers (EUPs) have End-user programmers (EUPs) have plenty of programs to share.plenty of programs to share.

• EUPs’ programs include:– Spreadsheets

– Web forms

– Databases

– Macros

– Scripts

• With pictures on the fridge, WYSIWYG.• With programs, WYG is more than WYS

due to dynamic behavior of code.

Introduction

Much more complex than

pictures on the fridge!

44

Unfortunately, current sharing approaches Unfortunately, current sharing approaches for EUPs have serious limitations.for EUPs have serious limitations.

• “Point-to-point”– Go to the guru (in person, or via email) [Nar93, Seg04, Wie05]

– Problem: Not scalable; # links ~ O(#gurus * #EUPs)

– Result: Without the presence of a guru, programs are dead

• “Multicast”– Go to internet (web, newsgroups, special sites) [Ros04, Ros05]

– Problem: Lots of irrelevant, hard-to-adapt material

– Result: Real reuse is limited to ideas & data (e.g.: images)

• Professionals’ traditional approach is a “repository“– Organizational or global (e.g.: SourceForge)

Introduction

55

EUPs’ “real work” is EUPs’ “real work” is not programming.not programming.

• Professional programmers (PPs): program = deliverable

• End-user programmers (EUPs): program = means to end

• PPs often have incentives to plan for reusability.• EUPs often do not. [Ros04, Seg04, Wie05]

• Thus, EUPs allocate very little time…– For designing reusable “components”– For creating documentation– For getting training in software design

• I will discuss implications for repository use by EUPs…

Introduction

66

This talk develops a to-do list.This talk develops a to-do list.

• Adapting the repository approach for EUPs will require:1. Post-hoc abstraction mechanisms

2. A way to easily document abstractions

3. A way to cloak private data in programs

4. Integration of trustworthiness into repositories

• Objective:– To review a body of interesting problems & approaches

that I discovered while reading the literature about EUPs.

• This will not be a thesis to-do list.– But the material does have implications for my research.

Outline

77

Code is much easier to reuse if it is Code is much easier to reuse if it is “wrapped” in an abstraction.“wrapped” in an abstraction.

• Would you prefer a pile of code, or a crisp API?

• PPs can share libraries– Write, compile, jar/zip up class libraries

– Other PPs instantiate objects, call parameterized methods

• Tools often only let EUPs share whole programs– How to “call” a reusable spreadsheet, web form, or macro?

• Also, EUPs lack incentives to design for reuse [Seg04, Wie05]

Abstractions

88

Many research tools enable EUPs to create Many research tools enable EUPs to create functional and data abstractions.functional and data abstractions.

Abstractions

Environment Domain Functional abstractions Data abstractions

AutoHAN [Bla01] Home automationChannel Cubes can map to scripts

that call functions on appliances.

Aggregate Cubes can represent a collection of other Media Cubes.

BOOMS [Bal02] Music editing Functions record series of music edits.Structures contain notes and

phrases.

Forms/3 [Jon03] Spreadsheet designA function can be implemented as a

mini-spreadsheet.Types are structured collections of

cells and graphical objects.

Gamut [Mcd99] Game designBehaviors are learned from positive

and negative examples.Decks of cards serve as graphical

containers with properties.

Janus [Fis90] Floor plan designCritic rules encode algorithms for

deciding if a floor plan is “good.”Instances of classes may possess

attributes and sub-objects.

KidSim [Smi94] Simulation designGraphical rewrite rules describe agent

behavior.

Agents may possess properties and are cloned for new instances.

Lapis [Mil02] Text editing Scripts automate a series of edits.Text patterns can contain sub-

structure.

Pursuit [Mod94] File managementScripts automate a series of

manipulations.Filter sets contain files and folders.

QUICK [Dou90] UI designActions may be associated with

objects (that are then cloned).Objects may have attributes and

be cloned and/or aggregated.

TEXAO [Tex99] CADFormulas may drive values of

attributes on cloneable objects.Instances of classes may possess

attributes and sub-objects.

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To-do list, item #1To-do list, item #1

• Needed: a mechanism so EUPs can conveniently create abstractions that are smaller than whole programs – Possible approach: support abstraction after-the-fact by

adapting refactoring algorithms [Gal99, Gri98]

• E.g.: highlight a segment of code text, and tell the algorithm to make this code a function; it automatically determines the right parameters & writes a function

• Other algorithms can extract classes, create packages, extract parameters, etc.

– Extracted abstractions should be reusable across tools• A la Microsoft.NET…• E.g.: Shouldn’t a JavaScript function be callable from

spreadsheet cells, spreadsheet macros, and databases?

Abstractions

1010

Code is much easier to understand and Code is much easier to understand and reuse if it is documented.reuse if it is documented.

• Documentation uses “secondary notation” [Gre06]

• PPs can generate docs from JavaDoc.– Embedded within the code.

– Or stored on the web & referenced with a link in the code

– (Even better, they will soon have Design Fragments!)

• Some EUP tools lack good places to put documentation– E.g.: macros, spreadsheets, databases

• Another obstacle to documentation by EUPs:– EUPs lack incentives to write documentation [Seg04, Wie05]

Documentation

1111


• Needed: post-hoc abstraction mechanisms• Needed: a way to easily document EUPs’ abstractions

– Approach #1: Make code more human-readable (e.g.: Koala web macros look very like English) [Lit07]

• Ideally, this will make programsmore self-documenting

• (A very old approach)

Documentation

1212



– Approach #1: Make code more human-readable– Approach #2: Auto-generate code from English [Lie06]

• Very domain-specific• (an old dream)

Documentation

1313



– Approach #1: Make code more human-readable

– Approach #2: Auto-generate code from English

– Approach #3: Embed examples of data abstractions• E.g.: Embed examples to explain Lapis patterns [Mil02a]@DayOfMonth is Number equal to /[12][0-9]|3[01]|0?[1-9]/

ignoring nothing

@ShortMonth is Number equal to /1[012]|0?[1-9]/

ignoring nothing

@ShortYear is Number equal to /\d\d/

ignoring nothing

Date is flatten @ShortMonth

then @DayOfMonth

then @ShortYear

ignoring either Spaces

or Punctuation

Documentation

02/ 31-99 is a valid instance of this pattern

1414



– Approach #1: Make code more human-readable

– Approach #2: Auto-generate code from English

– Approach #3: Embed examples of data abstractions

– Approach #4: Make it easy to locate examples online• Take a page from Mica, a search tool for Java code [Sty06]

– Given a phrase (e.g.: “open secure socket”), Mica issues Google queries to locate code that demonstrates how to use Java APIs to open an SSL socket

• To consider: if I created a reusable spreadsheet abstraction, what would a good “how to use this” example look like?

Documentation

1515

EUPs’ programs often have embedded, EUPs’ programs often have embedded, unsharable data.unsharable data.

• In the PP case (e.g.: Java), the program source code does not contain data.

• Not so with many EUPs’ programs– E.g.: spreadsheets, web forms, databases

• It might be bad to share data with other EUPs.– Removing data would make spreadsheets less

understandable!

– Removing data is somewhat in conflict with using examples as a form of documentation.

Data cloaking

1616


• Needed: post-hoc abstraction mechanisms• Needed: a way to easily document abstractions• Needed: a way to “cloak” private data in EUPs’ programs

– Possible approach: privacy-preserving anonymization• Private data can be intentionally “damaged” in a way that

makes it less traceable back to an individual yet does not render the data worthless for other purposes. [Swe03]

– A method would be needed to help EUPs find data in their programs that should probably be anonymized (e.g.: social security & credit card numbers).

– Very hard cases exist, too (e.g.: Has AIDS? “Y” / “N”)• What do HIPAA, SOX, and other regulations have to say?

Data cloaking

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Code is more likely to be reused if it is Code is more likely to be reused if it is “trustworthy.”“trustworthy.”

Trust

Can you please be more specific?

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PPs have many techniques for evaluating PPs have many techniques for evaluating trustworthiness of code.trustworthiness of code.

• “High-ceremony” sources of evidence include: [Sca07][Sha03]

– Formal verification – Code generation by a trusted automatic generator– Systematic testing– Careful empirical studies

• High-ceremony sources of evidence require: [Sca07]

– Require fairly precise specifications– Require substantial investment of effort– May be unavailable– May be hard for EUPs to interpret

• ([Boo02] characterizes “high-ceremony software processes”)

Trust

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In real life™, we trust people and things In real life™, we trust people and things based on “low-ceremony” evidence.based on “low-ceremony” evidence.

Trust

Source of evidence Example References

Explicit formal roles You have to trust your company’s lawyer because he is the company lawyer.

[Gra00,Huy04,Jos07,Mar94]

Prior performance He has never let you down in the past. [Mar04,Sab03]

Models of motivation He cares about winning your case… so that he gets paid.

[Ram04]

Informal group membership He is a member of the Rotary Club. [Gra00,Jos07,Mar94,Tad03]

Reputation “Everybody” knows that he is a good lawyer. [Huy04,Jos07,Mar94,Tad03]

References He said to ask Judy if he is a good lawyer, and she affirms that he is.

[Gra00,Huy04,Mar94]

Certification The American Bar Association says that he meets the minimum criteria for lawyering.

[Gra00,Huy04,Sta01]

Social context You can always appeal if this lawyer loses the case.

[Has01,Jos07,Mar94]

2020

Code repositories have yet to tap most Code repositories have yet to tap most low-ceremony sources of evidence.low-ceremony sources of evidence.

Trust

Source of evidence Example Applications to Macros

Explicit formal roles EUPs may trust macros created by their organization’s system administrators.

Prior performance EUPs may trust macros with posted source code that other people have tried.

Models of motivation EUPs may trust macros from vendors that care about brand image.

Informal group membership EUPs may trust macros from EUPs who have similar interests or background.

Reputation EUPs may trust macros that earned anonymous votes of confidence.

References EUPs may trust macros that present a list of high-profile people who like them.

Certification EUPs may trust macros inspected and certified by a 3rd party.

Social context EUPs may trust macros that are actively maintained and implemented in a familiar language/platform.

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• Needed: post-hoc abstraction mechanisms• Needed: a way to easily document abstractions• Needed: a way to cloak private data in programs• Needed: integration of trustworthiness into repositories

– Promising approach: trust-based filtering in search tools

– Reputation and references have been used for finding…• Matlab code [Gul06]

• Spreadsheets [Bur02]

• Web services [Zen04]

• General software components [Bel99]

Trust

2222

This talk developed a to-do list.This talk developed a to-do list.

• If you want to help EUPs share programs, then develop:– Post-hoc abstraction mechanisms

– A way to easily document abstractions

– A way to cloak private data in programs

– Integration of trustworthiness into repositories

• For each item, there are promising approaches.• These approaches will need to be adapted to help EUPs.

Summary

2323

References (1)References (1)

[Bal02] M. Balaban, E. Barzilay, and M. Elhadad. Abstraction as a Means for End User Computing in Creative Applications. IEEE Transactions on Systems, Man and Cybernetics, Part A, 32, 6 (Nov. 2002), pp. 640-653.

[Bel99] C. Bellettini, E. Damiani, and M. Fugini. User Opinions and Rewards in Reuse-Based Development System. Proceedings of the 1999 Symposium on Software Reusability, 1999, pp. 151-158.

[Bla01] A. Blackwell and R. Hague. AutoHAN: An Architecture for Programming the Home. In Proceedings of the IEEE 2001 Symposia on Human Centric Computing Languages and Environments, 2001, pp. 150-157.

[Boo02] G. Booch. Developing the Future. Communications of the ACM, Vol. 44, No. 3, 2001, pp. 118-121.

[Bur02] M. Burnett. Software Engineering for Visual Programming Languages, Handbook of Software Engineering and Knowledge Engineering, World Scientific Publishing Company, Vol. 2, 2002, pp. 77-92.

[Dou90] S. Douglas, E. Doerry, and D. Novick. D. Quick: A User-Interface Design Kit for Non-Programmers. In Proceedings of the 3rd Annual ACM SIGGRAPH Symposium on User Interface Software and Technology, 1990, pp. 47-56.

[Fis90] G. Fischer and A. Girgensohn. End User Modifiability in Design Environments. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, 1990, pp. 183-192.

[Gal99] K. Gallagher and J. Lyle. Using Program Slicing in Software Maintenance. IEEE Transactions on Software Engineering, Vol. 17, No. 8, 1991, pp. 751-761.

References

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[Gra00] T. Grandison and M. Sloman. A Survey of Trust in Internet Applications. IEEE Communications Surveys and Tutorials, Vol. 3, No. 4, 2000, pp. 2-16.

[Gre06] T. Green, et al. Cognitive Dimensions: Achievements, New Directions, and Open Questions. Journal of Visual Languages and Computation, 17.4, 2006, pp. 328-365

[Gri98] W. Griswold, et al. Tool Support for Planning the Restructuring of Data Abstractions in Large Systems. IEEE Transactions on Software Engineering, Vol. 24, No. 7, July 1998, pp. 534-558.

[Gul06] N. Gulley. Improving the Quality of Contributed Software and the MATLAB File Exchange, Proceedings of the 2nd Workshop on End User Software Engineering (WEUSE II), 2006, pp. 8-9.

[Has01] R. Hastie and R. Dawes. Rational Choice in an Uncertain World: The Psychology of Judgment and Decision Making, Sage Publications, 2001.

[Huy04] T. Huynh, N. Jennings, and N. Shadbolt. Developing an Integrated Trust and Reputation Model for Open Multi-Agent Systems. In Proceedings of the 7th International Workshop on Trust in Agent Societies, 2004, pp. 65-74.

[Jon03] S. Jones, A. Blackwell, and M. Burnett. A User-Centred Approach To Functions in Excel. ICFP '03: Proceedings of the Eighth ACM SIGPLAN International Conference on Functional Programming, 2003, pp. 165-176.

[Jos07] A. Jøsang, R. Ismail, and C. Boyd. A Survey of Trust and Reputation Systems for Online Service Provision. Decision Support Systems, Vol. 43, No. 2, 2007, pp. 618-644.

[Lie06] H. Lieberman, H. Liu, and Y. Li. End-User Software Engineering in Natural Language, Proceedings of the 2nd Workshop on End User Software Engineering (WEUSE II), 2006, pp. 38-40.

References

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[Lit07] G. Little, T. Lau, J. Lin, E. Kandogan, E. Haber, and A. Cypher. Koala: Capture, Share, Automate, Personalize Business Processes on the Web. CHI’07: Proceedings of the 25th Conference on Human Factors in Computing Systems, 2007, to appear.

[Mar94] J. March. A Primer on Decision Making: How Decisions Happen, Free Press, 1994.

[Mcd99] R. McDaniel and B. Myers. Getting More Out of Programming-By-Demonstration. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, 1999, pp. 442-449.

[Mil02] R. Miller and B. Myers. LAPIS: Smart Editing with Text Structure. In CHI '02 Extended Abstracts on Human Factors in Computing Systems, 2002, pp. 496-497.

[Mil02a] R. Miller. Lightweight Structure in Text. PhD thesis, Computer Science Department, School of Computer Science, Carnegie Mellon University, 2002

[Mod94] F. Modugno and B. Myers. Pursuit: Graphically Representing Programs in a Demonstrational Visual Shell. In Proceedings of the CHI '94 Conference Companion on Human Factors in Computing Systems, 1994, pp. 455-456.

[Nar93] B. Nardi. A Small Matter of Programming, MIT Press, 1993.

[Ram04] S. Ramchurn, D. Huynh, and N. Jennings. Trust in Multi-Agent Systems. Knowledge Engineering Review, Vol. 19, No. 1, 2004, pp. 1-25.

[Ros04] M. Rosson, J. Ballin, and H. Nash. Everyday Programming: Challenges and Opportunities for Informal Web Development. Visual Languages and Human Centric Computing, 2004 IEEE Symposium on, 2004, pp. 123-130.

References

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[Ros05] M. Rosson, J. Ballin, and J. Rode. Who, What, and How: A Survey of Informal and Professional Web Developers. Proceedings of the 2005 IEEE Symposium on Visual Languages and Human-Centric Computing (VL/HCC'05), 2005, pp. 199-206.

[Sab03] J. Sabater. Trust and Reputation for Agent Societies. IIIA Monograph Series, Vol. 20, 2003.

[Sca07] C. Scaffidi and M. Shaw. An Inventory of Techniques that Predict Value from Design, working paper predictor-table-v2-7, Institute for Software Research, Carnegie Mellon University, Dec 8, 2007, http://www.cs.cmu.edu/~cscaffid/papers/predictor-table-v2-7.pdf

[Seg04] J. Segal. Professional End User Developers and Software Development Knowledge. Technical Report 2004/25, Department of Computing, Faculty of Mathematics and Computing, the Open University, Milton Keynes, United Kingdom, Oct 2004

[Sha03] M. Shaw. Writing Good Software Engineering Research Papers. Proceedings of the 25th International Conference on Software Engineering, 2003, pp. 726-736.

[Smi94] D. Smith, A. Cypher, and J. Spohrer. KidSim: Programming Agents without a Programming Language. Communications of ACM, 37, 7 (July 1994), pp. 54-67.

[Sta01] J. Stafford and K. Wallnau. Is Third Party Certification Necessary?. Proceedings of the 4th ICSE Workshop on Component–Based Software Engineering, 2001, pp. 33-40.

[Sty06] J. Stylos and B. Myers. Mica: A Web-Search Tool for Finding API Components and Examples. Proceedings of the Visual Languages and Human-Centric Computing (VL/HCC'06), 2006, pp. 195-202.

References

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[Swe03] L. Sweeney. Navigating Computer Science Research Through Waves of Privacy Concerns: Discussions among Computer Scientists at Carnegie Mellon University, Technical Report CMU-ISRI-03-102, July 2003.

[Tad03] S. Tadelis. Firm Reputation with Hidden Information. Economic Theory, Vol. 21, No. 2-3, Mar 2003, pp. 635-651.

[Tex99] G. Texier and L. Guittet. User Defined Objects Are First Class Citizens. In Proceedings of the 3rd International Conference on Computer-Aided Design of User Interfaces, 1999, pp. 231-244.

[Wie05] S. Wiedenbeck. Facilitators and Inhibitors of End-User Development by Teachers in a School Environment. IEEE Symposium on Visual Languages and Human-Centric Computing, 2005, pp. 215-222

[Zen04] L. Zeng, B. Benatallah, A. Ngu, and M. Dumas. QoS-Aware Middleware for Web Services Composition. IEEE Transactions on Software Engineering, Vol. 30, No. 5, 2004, pp. 311-327.

References

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Thank youThank you

• To Mary Shaw and Brad Myers for suggestions about helping EUPs understand and share programs.

• To ISR for the opportunity to present today.

• To NSF for funding.

• To www.epa.gov and www.pueblo.gsa.gov for images.

Thank You

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This literature inspired several ideas for This literature inspired several ideas for helping EUPs share topes.helping EUPs share topes.

• Tope = a package of executable software functions for recognizing, transforming, and equivalence-testing instances of a category of data– E.g.: recognize ###-###-#### and (###) ###-####

as phone numbers, transform between these formats, and test equivalence of values

• Post-hoc abstraction: creating topes from examples• Documentation: document by embedding example values• Data cloaking: topes can be used to find data for cloaking• Trust: annotate topes with meta-information containing

many low-ceremony sources of evidence

Implications for my research

helping end-user programmers share their creations (literature review)

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