Client-facing stages, data-facing phases
◈ 5 cardsThe SAF five-stage problem-solving process faces the client; CRISP-DM faces the data. Each PSP stage is served by one or two CRISP-DM phases.
Two processes, one project
Every SAF course frames work through the five-stage Problem-Solving Process (PSP): (1) assess the situation, (2) identify and analyse the issues, (3) develop and analyse alternatives, (4) decide and recommend, (5) communicate. It is the client's view of a project: what they need, what is wrong, what could be done, what you advise, how you tell them. AFM 112's stated outcome is that CRISP-DM supports that process. The pairing below is how this course reads that sentence.
The two are not rivals. The PSP is client-facing — its stages are named for what the client experiences. CRISP-DM is data-facing — its phases are named for what happens to the data. Lay them side by side and each PSP stage is served by one or two CRISP-DM phases.
Worked example — the Alberta store, in both vocabularies
| PSP stage | CRISP-DM phase(s) that serve it | What the client sees |
|---|---|---|
| 1 Assess the situation | business understanding | the question, and the $100 criterion |
| 2 Identify and analyse the issues | data understanding + data preparation | the data dictionary; "only two AB orders" |
| 3 Develop and analyse alternatives | modelling | the provincial comparison |
| 4 Decide and recommend | evaluation | "not yet — the AB figure cannot carry it" |
| 5 Communicate | deployment | the memo, the dashboard |
Stage 1 and business understanding are nearly the same activity under two names: Renata's objective, the resources and risks, the criterion. Stage 2 is where the data-facing process does more work than the client sees — two whole phases, understanding and preparation, sit under one client stage, because the client experiences "finding out what is wrong" as one step while the analyst experiences it as looking and then fixing. Stage 3, alternatives, is served by modelling: the comparison of provinces is the analysis of the alternative ("Alberta, or not"). Stage 4, decide and recommend, is evaluation — not modelling, where the numbers come from, and not deployment, where the recommendation is delivered. Stage 5, communicate, is deployment.
Why preparation has no stage of its own
A client never asks for a cleaned table; they ask what the issues are. Data preparation is invisible from the client side, which is exactly why it is the phase that analysts under-budget and the PSP does not name. In CRISP-DM it is usually the longest phase. Knowing that the client-facing process hides it is a practical warning: plan time for a stage the client will not see.
Complete the pairing
Cover the table. Decide and recommend ↔ ? Communicate ↔ ? Which PSP stage has two CRISP-DM phases under it, and which two? Then say in one sentence why the answer to "where do the numbers come from?" (modelling) is not the answer to "where is the recommendation made?" (evaluation).