A weak opening
“I analyzed data and made a dashboard.” This gives no question, source, inclusion rule or independently checkable result.
A stronger opening
“I compared attributed conversion efficiency across three fictional campaigns, calculated rates from aggregated counts and documented why these comparisons do not establish incremental lift.”
Why the stronger version works
It names the scope, independent work, method and evidence boundary. It does not claim a real employer, client impact or an outcome outside the extract.
Suggested repository structure
README with question and reproduction commands; data with dictionary and permissions; src with your implementation; tests with expected totals; outputs with chart/table and decision note. Keep answer keys separate from your own attempt.
Evidence to annotate
Spend EUR500, clicks 900, attributed conversions 54, conversion rate 6%, spend/conversion EUR9.26. Search spend 270/27=10; Social 180/9=20; Email 50/18=2.78 EUR/conversion. Explain why each validation exists. Include one failed check you investigated and how you resolved it, rather than hiding all intermediate problems.
Your independent task
Reproduce the analysis yourself, then add a documented extension or alternative presentation. Credit the original fixture and explain your contribution. No order values, user overlap or randomized comparison are provided. Do not claim ROAS, profit or causal lift.
Career note
Portfolio examples and resume guidance do not guarantee interviews or a job. Use your own verified work; do not copy the sample as commercial experience.
Try the activity before reading its reference. Keep your sources, commands and assumptions with your work. Companion activities are unsaved self-practice and do not award a certificate or change lesson progress.