Focus: Users’ Stories & Use Cases

Preamble

Agile and phased development solutions are meant to solve different problems and therefore differ with artifacts and activities; that can be illustrated by requirements, understood as words in progress for the former, etched statements for the latter.

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Running Stories (Kara Walker)

Ignoring that distinction is to make stories stutter from hiccupped iterations, or phases sputter along ripped milestones.

Agile & Phased Tell Different Stories Differently

As illustrated by ill-famed waterfall, assuming that requirements can be fully set upfront often put projects at the hazards of premature commitments; conversely, giving free rein to expectations could put requirements on collision courses.

That apparent dilemma can generally be worked out by setting apart business outlines from users’ stories, the latter to be scripted and coded on the fly (agile), the former analysed and documented as a basis for further developments (phased). To that end project managers must avoid a double slip:

  • Mission creep: happens when users’ stories are mixed with business models.
  • Jump to conclusions: happens when enterprise business cases prevail over the specifics of users’ concerns.

Interestingly, the distinction between purposes (users concerns vs business functions) can be set along one between language semantics (natural vs modeling).

Semantics: Capture vs Analysis

Beyond methodological contexts (agile or phased), a clear distinction should be made between requirements capture (c) and modeling (m): contrary to the former which translates sequential specifications from natural to programming (p) languages without breaking syntactic and semantic continuity, the latter carries out a double translation for dimension (sequence vs layout) and language (natural vs modeling.)

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Semantic continuity (c>p) and discontinuity (c>m>p)

The continuity between natural and programming languages is at the root of the agile development model, enabling users’ stories to be iteratively captured and developed into code without intermediate translations.

That’s not the case with modeling languages, because abstractions introduce a discontinuity. As a corollary, requirements analysis is to require some intermediate models in order to document translations.

The importance of discontinuity can be neatly demonstrated by the use of specialization and generalization in models: the former taking into account new features to characterize occurrences (semantic continuity), the latter consolidating the meaning of features already defined (semantic discontinuity).

Confusion may arise when users’ stories are understood as a documented basis for further developments; and that confusion between outcomes (coding vs modeling) is often compounded by one between intents (users concerns vs business cases).

Concerns: Users’ Stories vs Business Cases

As noted above, users’ stories can be continuously developed into code because a semantic continuity can be built between natural and programming languages statements. That necessary condition is not a sufficient one because users’ stories have also to stand as complete and exclusive basis for applications.

Such a complete and exclusive mapping to application is de-facto guaranteed by continuous and incremental development, independently of the business value of stories. Not so with intermediate models which, given the semantic discontinuity, may create back-doors for broader concerns, e.g when some features are redefined through generalization. Hence the benefits of a clarity of purpose:

  • Users’ stories stand for specific requirements meant to be captured and coded by increments. Documentation should be limited to application maintenance and not confused with analysis models.
  • Use cases should be introduced when stories are to be consolidated or broader concerns factored out , e.g the consolidation of features or business cases.

Sorting out the specifics of users concerns while keeping them in line with business models is at the core of business analysts job description. Since that distinction is seldom directly given in requirements, it could be made easier if aligned on modeling options: stories and specialization for users concerns, models and generalization for business features.

From Stories to Cases

The generalization of digital environments entails structural and operational adjustments within enterprise architectures.

At enterprise level the integration of homogeneous digital flows and heterogeneous symbolic representations can be achieved through enterprise architectures and profiled ontologies. But that undertaking is contingent on the way requirements are first dealt with, namely how the specifics of users’ needs are intertwined with business designs.

As suggested above, modeling schemes could help to distinguish as well as consolidate users narratives and business outlooks, capturing the former with users’ stories and the latter with use cases models.

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Use cases describe the part played by systems taking into account all supported stories.

That would neatly align means (part played by supporting systems) with ends (users’ stories vs business cases):

  • Users’ stories describe specific objectives independently of the part played by supporting systems.
  • Use cases describe the part played by systems taking into account all supported stories.

It must be stressed that this correspondence is not a coincidence: the consolidation of users’ stories into broader business objectives becomes a necessity when supporting systems are taken into account, which is best done with use cases.

Aligning Stories with Cases

Stories and models are orthogonal descriptions, the former being sequenced, the latter laid out; it ensues that correspondences can only be carried out for individuals uniformly identified (#) at enterprise and systems level, specifically: roles (aka actors), events, business objects, and execution units.

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Crossing cases with stories: events, roles, business objects, and execution units must be uniformly and consistently identified (#) .

It must be noted that this principle is supposed to apply independently of the architectures or methodologies considered.

With continuity and consistency of identities achieved at architecture level, the semantic discontinuity between users’ stories and models (classes or use cases) can be managed providing a clear distinction is maintained between:

  • Modeling abstractions, introduced by requirements analysis and applied to artifacts identified at architecture level.
  • The semantics of attributes and operations, defined by users’ stories and directly mapped to classes or use cases features.
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From Capture to Analysis: Abstractions introduce a semantic discontinuity

Finally, stories and cases need to be anchored to epics and enterprise architecture.

Business Cases & Enterprise Stories

Likening epics to enterprise stories would neatly frame the panoply of solutions:

  • At process level users’ stories and use cases would be focused respectively on specific business concerns and supporting applications.
  • At architecture level epics and business cases would deal respectively with business models and objectives,  and supporting systems capabilities.
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A Squared frame for enterprise architectures governance

That would provide a simple yet principled basis for enterprise architectures governance.

Further Reading

External Links

Transcription & Deep Learning

Humans looking for reassurance against the encroachment of artificial brains should try YouTube subtitles: whatever Google’s track record in natural language processing, the way its automated scribe writes down what is said in the movies is essentially useless.

A blank sheet of paper was copied on a Xerox machine.
This copy was used to make a second copy.
The second to make a third one, and so on…
Each copy as it came out of the machine was re-used to make the next.
This was continued for one hundred times, producing a book of one hundred pages. (Ian Burn)

Experience directly points to the probable cause of failure: the usefulness of real-time transcriptions is not a linear function of accuracy because every slip can be fatal, without backup or second chance. It’s like walking a line: for all practical purposes a single misunderstanding can throw away the thread of understanding, without a chance of retrieve or reprieve.

Contrary to Turing machines, listeners have no finite states; and contrary to the sequence of symbols on tapes, tales are told by weaving together semantic threads. It ensues that stories are work in progress: readers can pause to review and consolidate meanings, but listeners have no other choice than punting on what comes to they mind, hopping that the fabric of the story will carry them out.

So, whereas automated scribes can deep learn from written texts and recorded conversations, there is no way to do the same from what listeners understand. That’s the beauty of story telling: words may be written but meanings are renewed each time the words are heard.

Further Reading

The Agility of Words

Preamble

Oral cultures come with implicit codes for the repetition of words and sentences, making room for some literary hide-and-seek between the storyteller and his audience.

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Stories Waiting to Happen

Could such narrative schemes be employed for users’ stories to open out the dialog between users (the storytellers) and business analysts (the listeners).

Open Storytelling

To begin with fiction, authors are meant to tell stories for readers ready to believe them at least while they are reading.

For young readers yet unable to suspend their disbelief, laser-disc games of the last century already gave post-toddlers a free hand to play with narratives.

But when the same scheme has been tried with grown-ups it has fizzled out: what would be the point of buying a story if you have to make it yourself ? the answer of agile business analysts is that users’ stories may be more pliable than budgets.

Tell Once, Tell Twice, Think Again

That’s what has just happened to “Hamlet on the Holodeck: The Future of Narrative in Cyberspace”, first published by Janet H. Murray twenty years ago with qualified ado, and now making a new debut, unedited yet clever as ever. That suggests both an observation and an interrogation.

For one, and notwithstanding readers consideration, a good story, fiction or otherwise, remains a good story which may be better appreciated in different circumstances. Then, considering the weighty mutation of circumstances since the book first appearance, the interrogation is about probable cause: should the origin of the rebirth to be looked for in technological advances, in the readers’ mind of that specific (non-fiction) book, or in the readiness of (fiction) books readers to collaborate in story building

Alternates in Narrative

As probable cause for new narrative ways, technology obviously comes first due to its means to change the relationship between readers and stories: breakthroughs in artificial intelligence, deep-learning, and computational linguistics have opened paths barely conceivable twenty years ago.

As a collateral effect of the technological revolution, opportunity may explain the renewed interest of Janet Murray’s likely readers: issues that were hardly broached before the initial publishing are now routinely mooted in the literati cognosphere.

Finally, on a broader social perspective, changes may have altered the motivation of fiction aficionados, bringing new relevancy to Janet Murray’s intuitions: as farcically illustrated by the uncritical audiences for alternative facts, the perception of reality may have been transformed by the utter sway of social networks.

Back to a literary perspective, evidences seem to point to the status of stories with regard to reality:

  • When embedded in games, stories don’t pretend to anything. On that ground changes are driven by players’ decisions regarding events or characters’ options that only affect the narratives of a plot defined upfront.
  • When set as fictions, stories, however preposterous, are meant to stand on their own ground. The meanings given to events and options are constitutive of the plot, and readers’ decisions are driven by their understanding of facts and behaviors.

So, Google’s AlphaGo may have overturned the grounds for the first category, but stories are not games and the only variants that count are the ones affecting understanding. More so for stories that use fictional realities to tell what should be.

Heed & Lead in Users’ Stories

Users’ stories are the agile answer to the challenge of elusive requirements. Definitively a cornerstone of the agile approach to software engineering, users’ stories are meant to deal with the instability of requirements, in contours as well as detours.

With regard to contours, users’ stories explore the space of requirements through successive iterations rooted into clearly identified users’ needs. Whereas the backbone (the plot) is set by stakeholders (the authors), the scope doesn’t have to be revealed upfront but can be progressively discovered through interactions between users (the storytellers) and analysts (the listeners).

But detours are where alternates in narratives may really prove themselves by helping to adjust users’ needs (the narratives) to business objectives (the plot). As a consequence changes suggested by analysts should not be limited to users’ options and ergonomy but may also concern the meaning of facts and behaviors. Along that reasoning users’ stories would use the agility of words to align the meanings of new business applications with the ones set by business functionalities already supported by systems.

Further Reading

External Links