Lesson ProgressPhase 4 of 6
Phase 4Independent Practice
Independent Practice: Outliers and Data Quality
Apply Descriptive statistics: mean, median, standard deviation, and z-scores independently to solve authentic business problems
Outlier Detection Mastery Practice
Calculate z-scores and identify outliers. Get 4 correct to show mastery.
Mastery target: 4 correct out of 5 | Current: 0 correct
Mean = $15.00, Std Dev = $5.00, Transaction = $25.00
Mean = $12.50, Std Dev = $3.25, Transaction = $3.00
Mean = $20.00, Std Dev = $8.00, Transaction = $44.00
Mean = $10.00, Std Dev = $2.50, Transaction = $10.00
Mean = $18.00, Std Dev = $4.50, Transaction = $9.00
Remember the Rules
Z-Score Formula
z = (x - μ) / σ
The ±2 Rule
|z| greater than 2 = outlier