{"id":395,"date":"2017-05-15T15:03:18","date_gmt":"2017-05-15T15:03:18","guid":{"rendered":"http:\/\/imalogic.com\/blog\/?p=395"},"modified":"2021-12-08T02:02:39","modified_gmt":"2021-12-08T02:02:39","slug":"use-case-points","status":"publish","type":"post","link":"https:\/\/imalogic.com\/blog\/2017\/05\/15\/use-case-points\/","title":{"rendered":"Use Case Points"},"content":{"rendered":"

<\/p>\n

\u201cYou can not plan if you can not measure <\/b><\/span><\/span><\/h2>\n
AND <\/b><\/span><\/span><\/h2>\n
IF YOU FAIL TO PLAN YOU HAVE PLANNED TO FAIL.\u201d<\/b><\/span><\/span><\/h2>\n
Introduction & Motivation<\/h1>\n
\n
Une large proportion des d\u00e9veloppements de syst\u00e8mes informatiques :<\/span><\/span><\/span><\/li>\n<\/ul>\n
\u2013 D\u00e9passe<\/span><\/span><\/span> les budgets, ou <\/span><\/span><\/span><\/p>\n
\u2013 Est d\u00e9livr\u00e9e apr\u00e8s le temps d\u00e9fini ou pas d\u00e9livr\u00e9 du tout, ou <\/span><\/span><\/span><\/p>\n
\u2013 N\u2019est pas d\u00e9livr\u00e9e avec les fonctionnalit\u00e9s sp\u00e9cifi\u00e9es.<\/span><\/span><\/span><\/p>\n
\n
Afin de planifier, il est n\u00e9cessaire de disposer d\u2019estimations fiables de l\u2019effort \u00e0 fournir (\u201cEstimation Exacte\u201d \u00e9tant une impossibilit\u00e9 par nature).<\/span><\/span><\/span>
\n
\n<\/li>\n<\/ul>\n
Peut-on utiliser les mod\u00e8les de cas d\u2019utilisation pour r\u00e9aliser et\/ou am\u00e9liorer ces estimations ?<\/span><\/span><\/strong><\/span><\/p>\n
\n
Approche pour l\u2019am\u00e9lioration de l\u2019estimation<\/span><\/h1>\n
Bonne pratique pour l\u2019estimation : <\/span><\/span><\/span><\/p>\n
\n
\n
NE JAMAIS UTILISER UNE SEULE\u00a0<\/b><\/span><\/span>M\u00c9THODE<\/b><\/span><\/p>\n<\/li>\n<\/ul>\n
\n
Combiner l\u2019estimation de diff\u00e9rents experts et les strat\u00e9gies d\u2019estimation.<\/span><\/span><\/span><\/li>\n
Faire des estimations \u201ctop-down\u201d et \u201cbottom-up\u201d de mani\u00e8re ind\u00e9pendante.<\/span><\/span><\/span><\/li>\n
Justifier et critiquer les estimations.<\/span><\/span><\/span><\/li>\n<\/ul>\n
Afin d\u2019am\u00e9liorer les estimations r\u00e9alis\u00e9es par des experts, l\u2019utilisation de m\u00e9thodes est relevante. <\/span><\/span><\/span><\/p>\n
\n
Un <\/span><\/span><\/span>use case model<\/b><\/span><\/span><\/span> d\u00e9finit la \u00ab\u00a0port\u00e9e fonctionnelle\u00a0\u00bb du syst\u00e8me \u00e0 d\u00e9velopper. <\/span><\/span><\/span><\/li>\n<\/ul>\n
\n
\n
La \u00ab\u00a0port\u00e9e fonctionnelle\u00a0\u00bb est la base de l\u2019estimation top-down<\/span><\/span><\/p>\n<\/li>\n<\/ul>\n
\n
Les param\u00e8tres de l\u2019estimation peuvent d\u00e9riv\u00e9s d\u2019un <\/span><\/span><\/span>use case model<\/b><\/span><\/span><\/span>.<\/span><\/span><\/span><\/li>\n<\/ul>\n
\n
Suivant un processus de d\u00e9veloppement dirig\u00e9 par des use cases, un use case de haut niveau est disponible au commencement, tandis qu\u2019un use case d\u00e9taill\u00e9 est disponible au d\u00e9but de la phase d\u2019\u00e9laboration.<\/span><\/span><\/span><\/li>\n<\/ul>\n
\n
Plusieurs compagnies utilisent l\u2019approche \u201cuse case model\u201d dans l\u2019estimation de leur processus.<\/span><\/span><\/span>\n
\n<\/p><\/li>\n<\/ul>\n
\n
\n
\n
Comment peut-on utiliser de la meilleure fa\u00e7on un use case model dans l\u2019estimation de l\u2019effort pour le d\u00e9veloppement logiciel ?<\/b><\/span><\/span><\/span><\/p>\n<\/li>\n<\/ul>\n
\n
La m\u00e9thode d\u2019estimation des Use Case Points <\/span><\/h1>\n
La technique des \u201cUse Case Points\u201d a \u00e9t\u00e9 d\u00e9velopp\u00e9e sur base de celle des \u00abFunction Points\u00bb en 1993 par Gustav Karner lorsqu\u2019il travaillait chez Objectory AB et ce sous la supervision d\u2019Ivar Jacobson. <\/span><\/span><\/p>\n
Cette technique de \u201cuse case points\u201d est en fait une \u00e9volution des \u00abFunction Points\u00bb mieux adapt\u00e9e pour des projets orient\u00e9s objets dans le cadre desquels les fonctionnalit\u00e9s du syst\u00e8me sont exprim\u00e9es en \u00abuse cases\u00bb. Cette m\u00e9thode est impl\u00e9ment\u00e9e en utilisant un tableau Excel.<\/span><\/span><\/span><\/p>\n
Quelques r\u00e9sultats de cas d\u2019\u00e9tude<\/span><\/h1>\n\n\n\n\n\n\n\n\n<\/colgroup>\n\n\n\n\n\n\n\n\n

Company<\/span><\/span><\/td>\n \n
Project<\/span><\/span><\/p>\n<\/td>\n
\n
Use Case Estimate<\/span><\/span><\/p>\n
(in hours)<\/span><\/span><\/p>\n<\/td>\n
\n
Expert Estimate<\/span><\/span><\/p>\n<\/td>\n
\n
Actual Effort<\/span><\/span><\/p>\n<\/td>\n
\n
Deviation use case est.<\/span><\/span><\/p>\n<\/td>\n
\n
Deviation exp. est.<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n
Mogul<\/span><\/span><\/td>\n \n
A<\/span><\/span><\/p>\n<\/td>\n
\n
2550<\/span><\/span><\/p>\n<\/td>\n
\n
2730<\/span><\/span><\/p>\n<\/td>\n
\n
3670<\/span><\/span><\/p>\n<\/td>\n
\n
-31%<\/span><\/span><\/p>\n<\/td>\n
\n
-26%<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n
Mogul<\/span><\/span><\/td>\n \n
B<\/span><\/span><\/p>\n<\/td>\n
\n
2730<\/span><\/span><\/p>\n<\/td>\n
\n
2340<\/span><\/span><\/p>\n<\/td>\n
\n
2860<\/span><\/span><\/p>\n<\/td>\n
\n
-5%<\/span><\/span><\/p>\n<\/td>\n
\n
-18%<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n
Mogul<\/span><\/span><\/td>\n \n
C<\/span><\/span><\/p>\n<\/td>\n
\n
2080<\/span><\/span><\/p>\n<\/td>\n
\n
2100<\/span><\/span><\/p>\n<\/td>\n
\n
2740<\/span><\/span><\/p>\n<\/td>\n
\n
-24%<\/span><\/span><\/p>\n<\/td>\n
\n
-23%<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n
CGE&Y<\/span><\/span><\/td>\n \n
A<\/span><\/span><\/p>\n<\/td>\n
\n
10831<\/span><\/span><\/p>\n<\/td>\n
\n
7000<\/span><\/span><\/p>\n<\/td>\n
\n
10043<\/span><\/span><\/p>\n<\/td>\n
\n
+8%<\/span><\/span><\/p>\n<\/td>\n
\n
-30%<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n
CGE&Y<\/span><\/span><\/td>\n \n
B<\/span><\/span><\/p>\n<\/td>\n
\n
14965<\/span><\/span><\/p>\n<\/td>\n
\n
12600<\/span><\/span><\/p>\n<\/td>\n
\n
12000<\/span><\/span><\/p>\n<\/td>\n
\n
+25%<\/span><\/span><\/p>\n<\/td>\n
\n
+5%<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n
IBM<\/span><\/span><\/td>\n \n
A<\/span><\/span><\/p>\n<\/td>\n
\n
4086<\/span><\/span><\/p>\n<\/td>\n
\n
2772*<\/span><\/span><\/p>\n<\/td>\n
\n
3360<\/span><\/span><\/p>\n<\/td>\n
\n
+22%<\/span><\/span><\/p>\n<\/td>\n
\n
-18%<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
Constatation :<\/h2>\n
La m\u00e9thode des use case points produit des estimations proches de l\u201deffort actuel dans les diff\u00e9rents projets.<\/span><\/span><\/span><\/p>\n
\n
Cela signifie que la m\u00e9thode des use case points peut \u00ab\u00a0supporter\/renforcer\u00a0\u00bb une expertise lorsqu\u2019un use case model existe pour le projet.<\/span><\/p>\n
\n
Pr\u00e9-requis pour appliquer la m\u00e9thode des UCP<\/h1>\n
\n
\n
Existence de Use Cases (pas \u00e9vident au d\u00e9but d\u2019un projet)<\/span><\/span><\/span><\/p>\n<\/li>\n<\/ul>\n
\n
\n
Le use case model doit \u00eatre correct:<\/span><\/span><\/span><\/p>\n<\/li>\n<\/ul>\n
\n
\n
\n
\n
Il doit inclure les exigences (requirements) fonctionnelles de tous les groupes d\u2019utilisateurs. <\/span><\/span><\/span><\/p>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
\n
\n
\n
\n
La difficult\u00e9 principale \u00e9tant l\u2019acc\u00e8s \u00e0 des experts li\u00e9s \u00e0 chaque domaine, motiv\u00e9s et exp\u00e9riment\u00e9s.<\/span><\/span><\/p>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
\n
\n
Niveau de d\u00e9tail appropri\u00e9:<\/span><\/span><\/p>\n<\/li>\n<\/ul>\n
\n
\n
\n
\n
Le use case model doit \u00eatre d\u00e9crit \u00e0 un niveau appropri\u00e9 de d\u00e9tail. La principale difficult\u00e9 \u00e9tant d\u2019obtenir des use cases \u00e9quilibr\u00e9s et \u00e9viter des expansions \u201dinfinies\u201d. Les solutions possibles sont l\u2019utilisations de \u201dGuidelines\u201d, de bons exemples de use case models.<\/span><\/span><\/span><\/p>\n<\/li>\n
\n
\u00a0Si nous supposons que les exigences sont d\u00e9finies comme un ensemble de cas d\u2019utilisation, alors on peut utiliser la m\u00e9thode UCP (Use Case Points) comme base pour l\u2019estimation de l\u2019Effort\/Co\u00fbt<\/span><\/span><\/span><\/p>\n<\/li>\n<\/ul>\n<\/li>\n
\n
\u00c9tapes dans une estimation \u00ab\u00a0Use Case Points\u00a0\u00bb<\/h1>\n<\/li>\n<\/ul>\n
\n
\n
le diagramme suivant montre les diff\u00e9rentes \u00e9tapes dans une estimation \u201cUse Case Points\u201d.<\/p>\n
$\"\"$ <\/a><\/p><\/li>\n<\/ul>\n
\n
Des Use Case on va retirer les Unadjusted Use Case Points .
\nLes \u201cUnadjusted Use Case Points\u201d sont les points d\u00e9riv\u00e9s directement de la complexit\u00e9 des use cases et du nombre et type d\u2019acteurs impliqu\u00e9s.<\/span><\/span><\/span><\/li>\n<\/ul>\n
\n
Des UUC Points on va d\u00e9terminer les Adjusted Use Case Points en multipliant les UUC Points par des facteurs de complexit\u00e9. <\/span><\/span><\/span><\/li>\n<\/ul>\n
\n
Enfin associant un nombre d\u2019heures pour chaque AUCP, on pourra obtenir une estimation en Jours Homme.<\/span><\/span><\/span><\/li>\n<\/ul>\n
Couverture des \u201cUse Case Points\u201d<\/h1>\n
Les \u201cUse Case Points\u201d peuvent \u00eatre utilis\u00e9s pour estimer la charge de travail n\u00e9cessaire \u00e0 la r\u00e9alisation du design d\u00e9taill\u00e9, de l\u2019impl\u00e9mentation, et des tests unitaires et d\u2019int\u00e9gration, pour un syst\u00e8me dont les besoins sont exprim\u00e9s en use cases.<\/span><\/span><\/p>\n
Sch\u00e9matiquement la couverture des \u201cUse Case Points\u201d est la suivante:<\/span><\/span><\/p>\n
\n
\n\n\n\n<\/colgroup>\n\n\n\n\n\n\n\n\n\n

Inclus<\/strong><\/span><\/td>\n Non inclus<\/strong><\/span><\/td>\n<\/tr>\n
<\/td>\n Gestion du projet <\/span><\/strong><\/td>\n<\/tr>\n
\u00a0<\/span><\/strong><\/td>\n Analyse<\/span><\/strong><\/td>\n<\/tr>\n
Design d\u00e9taill\u00e9<\/strong><\/span><\/td>\n <\/td>\n<\/tr>\n
Impl\u00e9mentation<\/strong><\/span><\/td>\n \u00a0<\/strong><\/span><\/td>\n<\/tr>\n
Tests unitaires<\/strong><\/span><\/td>\n \u00a0<\/strong><\/span><\/td>\n<\/tr>\n
Tests d\u2019int\u00e9gration<\/strong><\/span><\/td>\n <\/td>\n<\/tr>\n
<\/td>\n Autres tests, tels que les tests de r\u00e9ception;
\nRoll out du syst\u00e8me;
\nDocumentation, autre que la documentation du design et de l\u2019impl\u00e9mentation;
\nGarantie<\/span><\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/dd>\n<\/dl>\n
Pour les \u00e9l\u00e9ments non inclus, les activit\u00e9s sont estim\u00e9es \u00e0 l\u2019aide d\u2019experts ayant men\u00e9 des projets d\u2019envergure similaire.<\/span><\/span><\/p>\n
Calcul du budget approximatif<\/h1>\n
Le nombre de jours homme sera multipli\u00e9 par le jour standard (en EUR par jour) afin d\u2019obtenir un budget approximatif.<\/span><\/span><\/p>\n
D\u00e9termination de la dur\u00e9e du projet<\/h1>\n
Le rapport Charge \u2013 D\u00e9lai d\u00e9pend de divers facteurs.<\/span><\/span><\/p>\n
1. Qui dit augmentation de la taille dit augmentation besoins coordination et augmentation risques incoh\u00e9rence<\/span><\/span><\/p>\n
2. Dur\u00e9e en mois > Nombre maximum de personnes dans l\u2019\u00e9quipe <\/span><\/span><\/p>\n
3. Pour les petits projets entre 3 MH et 30 MH (Mois\/Homme), nous avons :<\/span><\/span><\/p>\n
\n
Dur\u00e9e minimum conseill\u00e9e = 3,0. \u00b3\u221a<\/b>Mandays<\/span><\/span><\/span><\/b> = dur\u00e9e en jours<\/b><\/span><\/li>\n
Dur\u00e9e minimum conseill\u00e9e = 2,50. \u00b3\u221a<\/b>M\/H<\/span><\/span><\/span><\/b>= dur\u00e9e en ann\u00e9e<\/b><\/span><\/li>\n<\/ul>\n
4. La r\u00e9partition de charge est progressive : int\u00e9gration progressive de personnel, dissym\u00e9trie d\u00e9but\/fin<\/span><\/span><\/p>\n
Ces \u00e9l\u00e9ments sortent de la m\u00e9thode des use case points.<\/span><\/span><\/p>\n
On peut cependant donner la r\u00e9partition de l\u2019effort suivante:<\/span><\/span><\/p>\n
$\"\"$ <\/a><\/p>\n
La m\u00e9thode des UCP ne traitant que du design, de l\u2019impl\u00e9mentation et des tests, on peut arriver \u00e0 un total global \u00e0 l\u2019aide d\u2019une r\u00e8gle de 3.<\/strong><\/p>\n
<\/p>\n<\/body>","protected":false},"excerpt":{"rendered":"
\u201cYou can not plan if you can not measure AND IF YOU FAIL TO PLAN YOU HAVE PLANNED TO FAIL.\u201d<\/p>\n","protected":false},"author":1,"featured_media":399,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[65,7],"tags":[],"class_list":["post-395","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-analyse","category-coding"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/imalogic.com\/blog\/wp-content\/uploads\/2017\/05\/bean.jpg?fit=500%2C378&ssl=1","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p8J21V-6n","jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/posts\/395","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/comments?post=395"}],"version-history":[{"count":2,"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/posts\/395\/revisions"}],"predecessor-version":[{"id":981,"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/posts\/395\/revisions\/981"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/media\/399"}],"wp:attachment":[{"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/media?parent=395"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/categories?post=395"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/imalogic.com\/blog\/wp-json\/wp\/v2\/tags?post=395"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

Calcul du budget approximatif<\/h1>\nLe nombre de jours homme sera multipli\u00e9 par le jour standard (en EUR par jour) afin d\u2019obtenir un budget approximatif.<\/span><\/span><\/p>\n

Calcul du budget approximatif<\/h1>\n
Le nombre de jours homme sera multipli\u00e9 par le jour standard (en EUR par jour) afin d\u2019obtenir un budget approximatif.<\/span><\/span><\/p>\n