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Data foundations

Walmart — Purchase Behaviour with CLT & Confidence Intervals

Statistical study of customer transactions: compared spending across gender, age and marital status using bootstrapping, the Central Limit Theorem and confidence intervals to back marketing decisions with evidence.

Bootstrapped CIs
3 customer segments
PythonPandasStatisticsCLTHypothesis Testing

Problem

Do different customer groups really spend differently on Black Friday — or is it just noise?

Approach

  • Cleaned and explored the transaction dataset with Pandas.
  • Used bootstrapped sampling to build sampling distributions of mean spend per segment.
  • Applied the Central Limit Theorem to compute 90/95/99% confidence intervals.
  • Checked where intervals overlap to decide which differences are statistically meaningful.

Outcome

Clear, statistically validated recommendations on which segments to target — a foundation case study from my MS program.