{"id":95,"date":"2021-01-25T00:58:39","date_gmt":"2021-01-25T00:58:39","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-hccc-generalscience\/?post_type=chapter&p=95"},"modified":"2021-01-25T00:58:39","modified_gmt":"2021-01-25T00:58:39","slug":"9-data-uncertainty-error-and-confidence","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-hccc-generalscience\/chapter\/9-data-uncertainty-error-and-confidence\/","title":{"raw":"9. Data: Uncertainty, Error, and Confidence","rendered":"9. Data: Uncertainty, Error, and Confidence"},"content":{"raw":"
\r\n\r\nThe Olympic sport of biathlon (Figure 1) is a cross-country ski race of 20 km in which the athletes stop on four occasions to shoot 0.57 cm diameter bullets from a .22 caliber rifle at targets. The sport requires not only great endurance, but exceptional accuracy<\/a> as the athletes shoot on two occasions from the prone position (lying down) and on two occasions while standing. The targets the athletes aim for are all 50 m away, but the size varies to match the precision<\/a> expected of them; those targeted while shooting in the prone position are 4.5 cm in diameter while those targeted from the more difficult standing position are 11.5 cm in diameter. In both cases, however, the diameter of the target is many times larger than the diameter of the bullet itself \u2013 why?\r\n
\"Biathletes <\/a>
Figure 1:<\/strong> Biathletes in the shooting area of a competition. image \u00a9 Marc Schuelper<\/span><\/figcaption><\/figure>\r\nWhile the legend of Robin Hood splitting one arrow with another is well-known, it is also unrealistic. Biathlon targets are purposely sized many times larger than the bullets the athletes shoot to account for the inherent<\/a> error and uncertainty<\/a> involved in long distance riflery. Even the most skilled marksman cannot account for every variable<\/a> affecting the path of the bullet, like sudden gusts of wind or variations in air pressure. Shooting from the standing position involves even greater uncertainty, as indicated by the larger targets used, because even the simple rise and fall of an athlete's chest as they breathe can affect the aim of their rifle.\r\n\r\n<\/div>\r\n
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Categorizing uncertainty: Accuracy vs. precision<\/h2>\r\nScientific measurements also incorporate variability, and scientists report this as uncertainty<\/a> in an effort to share with others the level of error that they found acceptable in their measurements. But uncertainty in science does not imply doubt as it does in everyday use. Scientific uncertainty is a quantitative measurement of variability in the data<\/a>. In other words, uncertainty in science refers to the idea that all data have a range of expected values<\/a> as opposed to a precise point value. This uncertainty can be categorized in two ways: accuracy<\/a> and precision<\/a>.\r\n