STAT 110 1nd Edition Lecture 6 Outline of Previous Lecture I. Ethicsa. Federal Guidelines to Protect Human Subjects b. Research Involving Human Subjectsc. Violations of Ethical Guidelines II. Clinical Trialsa. Phases Outline of Current LectureI. Percent Change II. Measurement DefinitionsCurrent LectureI. Percent Changea. In order to calculate a percent change, use the following formula: i. Percent change = (current value - previous value) / previous value b. If your percent change is a positive number, your result is read as a percent increase, if your percent change is a negative number, your result is read as a percent decreaseII. Measurement Definitions a. We measure something when we assign a number or value to represent a property of that thing or personb. An instrument is used to make a measurement c. The result of a measurement is a numerical variable that has different values for the different subjects or things that we are measuring i. A variable is valid if it is a relevant or appropriate representation of the property we are trying to measure ii. A rate, such as a fraction, proportion, or percentage, is often a more valid measure than a count of occurrences d. A measurement has predictive validity when it can be used to predict similar results on properties that are similar to the ones we measure e. A measurement is biased if an error occurs systematically every time we take a measure. In other words, a measurement is biased if it overstates or understates the true value of a measurementThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.f. A measurement has random error is repeated measurements of the same property on the same subject give different results i. If random error is small, we say that a measurement is reliable. We can also say that when a measurement is reliable, it is repeatable. 1. We can use averages to improve