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10
Data Quality
KNOW THY DATA AND THYSELF
Imagine an airline hires us to consult as to why its customers are unhappy
according to survey data. We have strong reason to doubt that our client,
the airline, attracts especially grumpy passengers. Aer applying the sta-
tistical lessons we learned earlier in this book, we note the complaints
about bad ight crew service are coming from a particular cross section of
airports. We notice the same aircrews and airplanes cycle through other
airports, with few passenger satisfaction problems. e problems are with
these airports in particular. How could this be?
On a hunch, we suspect something is causing ...