In the Precision Teaching Book a great deal of information surrounded the difference between absolute amount of change and relative change. The Standard Celeration Chart offers relative change, the common nonstandard arithmetically scaled line chart uses absolute amount of change.To demonstrate the imperative we gain with relative change, please answer the following questions. If Bill Gates found a $10.00 bill, and a single mother of five children living in sub-Sahara Africa also found $10.00, for whom is it a more significant increase to his or her personal wealth? If a 42 pound, six-year-old girl is sick with strep throat and a 220 pound, 35-year-old man also has strep throat, who would significantly benefit by adding a daily, 180 mg dosage of Azithromycin (for five total days)?* Which atrocity was more significant, the 40,000,000 deaths from Mao Zedong’s rule where he starved his people and led a civil war or the 40,000,000 deaths from the 13th century Mongol Conquests? Bill Gates and the single mom both received the same amount of money (i.e., + $10.00), the six-year-old girl and the 35-year-old man both experienced the same milligram dosage, and the Mao Zedong rule and Mongol Conquest were equally catastrophic in terms of death toll (i.e., 40,000,000). Arithmetically scaled line charts portray and communicate the significance of educational change without context of where the change starts from.
Approaching the previous questions and embrace context provided by relative change we judge significance in a different light. If Bill Gates’ net worth comes to $56,000,000,000 and the single mom has a net worth of $100.00, finding a $10 bill would mean almost nothing to Bill Gates whereas the single mom has just come into the windfall of her lifetime. A 42 pound, six-year-old girl receiving a therapeutic dose will have a significant outcomes whereas a 220 pound, 35-year-old man may likely remain sick because the same dosage acts differently within his body due to weight. The Mao Zedong rule and the Mogul Conquests each killed 40 million people. When scaled for population size, however, Mao Zedong maintains a mid-20th-century equivalency of 40 million people who lost their lives while the adjusted Mongol Conquests would have led to 278,000,000 deaths making it the second most deadly atrocity in the 20th century (Pinker, 2011). Context matters.
*Azithromycin dosage guidelines: Children should take 12 milligrams (mg) per each kilogram they weight. For a 42 pound girl the recommended dosage works out to roughly 180 mg a day. Dosage recommendations for adults – 500 mg on day one and 1250 mg for days two through five.