Bring Emma to kindergarten: usage narrative (2)

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This Entry is dedicated to my project Use Case “Bring Emma to kindergarten”, Please read the project page first to get the general idea.

Well, besides ugly handwriting what else can we say about two usage narratives from the previous log? Let us put side by side all the artifacts described in two narratives like this:

Artifacts from narrative I call “First version” Artifacts from narrative I call “Second version”
1. Every working day
2. Reinis
3. more often Chris
4. around 8:30
5. Emma
6. bring to Kindergarten
7. washed
8. dressed up
9. fed breakfast
10. 5 minute walk
11. crossing no streets
1. prepare breakfast on previous evening
2. prepare dress
3. set alarm before sleep
4. get up when alarm goes off
5. prepare flakes
6. Emma
7. wake Emma if she’s still sleeping
8. Emma eats breakfast
9. Emma goes bathroom
10. we dress us up
11. we make hair
12. brush teeth
13. pack meal
14. dress up
15. not later than 8:20 leave house
16. Kindergarten registration till 8:30
17. Don’t forget Lunchbox!

Table 1: Artifacts from both narratives

Things I expected:

– Overall granularity will differ. This is visible by simply counting number of artifacts;

– Overall focus will differ. Every actor/stakeholder participating in use case has different goals thus focusing on slightly things

– Scope will differ. Guess this is the main reason requirements management is such a tedious job sometimes

Things I didn’t expect:

– Overall granularity differs only little. Second narrative has 6 additional artifacts but if we look more closely at the content – artifacts 1, 3 are not even covered in first narrative and artifacts 2, 5, 7, 11, 12, 13, 14, 15 and 17 just add to granularity. In following table I have tried to group artifacts based on type and what I got looks to me a good base for a use case outline. We’ve got actors, trigger, pre and post conditions along main success scenario.

– Scope differs only little. I took liberty to define what artifacts describe pre and post conditions of the use case before we made an In/Out List just to illustrate how both narratives differ in definition of scope. As you might see, second narrative defines preparations on the previous evening (dress, breakfast, alarm clock) as part of use case. Final definition of scope will be defined by in/out list as soon as we make it 🙂

– In both narratives focus is on phase between getting up and getting out of the house. What I mean is this – process of bringing Emma to kindergarten is vaguely mentioned only in first narrative (artifacts 10 and 11), is not mentioned in second narrative at all, but period between getting up and getting out of the house is covered by 3 artifacts in first narrative and by 9 artifacts respectively in second one (10 if you count validation artifact 17). This is kind of weird since getting to kindergarten and actually delivering Emma in kindergarten are rich of content (e.G. one have to find Emma’s locker, undress Emma, bring her to the right room and formally inform kindergarten personnel about Emma’s arrival, same is true for moving from house to kindergarten).

“First version” “Second version” Artifact type
[not covered] 1. prepare breakfast on previous evening
3. set alarm before sleep
Pre conditions
1. Every working day 4. get up when alarm goes off Trigger
4. around 8:30 15. not later than 8:20 leave house
16. Kindergarten registration till 8:30
17. Don’t forget Lunchbox!
Guarantees
2. Reinis
3. more often Chris
5. Emma
6. Emma Actors
6. bring to Kindergarten 7. wake Emma if she’s still sleeping
13. pack meal
Scenario
7. washed 9. Emma goes bathroom
11. we make hair
12. brush teeth
Scenario
8. dressed up 2. prepare dress
10. we dress us up
14. dress up
Scenario
9. fed breakfast 5. prepare flakes
8. Emma eats breakfast
Scenario
10. 5 minute walk
11. crossing no streets
[not covered] Scenario

Table 2: Aggregated narratives

Summary

I say, narratives deliver us up front certain amount of analytical data. Participation of multiple narrators probably help even further since there’s material to compare and differences are likely to hint out stuff that should be particularly elaborated upon (such as what sub processes narrators concentrate on, how they define scope etc.) I am practically able to build Use Case outline with only those two short narratives.

The true added value of narratives we will see in upcoming phases where I get my hands dirty and churn out the detail. At the moment I am keen to see how much of the structure I extracted out of narratives will remain at the end of this project.

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