When O'Connor and his colleagues broke down the results based on how well people were sticking to the exercise recommendations, an analysis not published in the JAMA paper, more striking differences emerged.

CNN: Moderate exercise safe, healthy for heart-failure patients

In the time that I have, I will set out the enormous differences in approach between the majority staff's and the minority staff's analysis.

CNN: Transcript: Schippers, Lowell briefings before Judiciary panel, part 2

This simple analysis reveals striking differences between the rich and most of the rest of the population.

BBC: The Wealth Gap - Inequality in Numbers

Based on morphological differences in the skull and bone structure, coupled with DNA analysis, the authors estimate that the Kha-Nyou diverged from other rodents millions of years ago.

BBC: Totally new to science

Researchers criticized its analysis for including sentences of probation, which they argued amplified the demographic differences.

WSJ: Wide Racial Divide in Sentencing

ETrade Supply performed an analysis on the iPhone 5 case, taking it apart and measuring it to quantify precise differences with current iPhone 4S and speculate about the intent of the changes.

FORBES: Apple's New iPhone Could Be Tall, Thin And Beautiful

Economists attempt to make the fudge factor as grounded in reality as possible, but instrumental variable analysis inevitably requires the analyst to give short shrift to the hard data and make assumptions about the differences between two populations, and how external factors (like insurance status) affect them.

FORBES: Why Medicaid is a Humanitarian Catastrophe

One recent analysis had to discard 75% of its research because it had failed to account for differences between the backgrounds and academic histories of pupils attending the schools.

ECONOMIST: Education