FANR 3000 1st Edition Lecture 2Outline of Last Lecture I. Data DefinitionsII. Types of DataOutline of Current Lecture I. Precision and AccuracyII. Types of error/biasIII. Describing and graphing data Current LectureI. Precision and Accuracya. Accuracy- the closeness of a measured value to the known/ true valueb. Precision- the closeness of 2 or more measurements to each otheri. Independent of accuracyThese 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.II. Types of error/biasa. Mistakes/gross errors- incorrect measurements due to carelessnessi. Reading the wrong number, ect.b. Systematic error (bias)- errors of the same size and magnitude with each subsequent measurementi. Bent compass needle, ect.ii. If the magnitude of error is known, accuracy can be improved by a correction/adjustment factor c. Random error- always present in a measurementi. Unpredictable fluctuations in the readings (due to equipment, weather, or reader) ii. Difficult to fix since errors vary in magnitudeIII. Describing and graphing dataa. Two primary methods of describing data:i. Graphically- histograms, bar graphs, pie charts, scatter plots, maps, ect.ii. Numerically- means, ranges, variability, confidence intervals, ect. b. Histogramsi. Frequency- quantitative/qualitative1. (1-n) number of observations in each variable class ii. Relative frequency- quantitative/ qualitative1. (0-1) fraction of the total observations in each variable classiii. Cumulative frequency- quantitative1. (1-n) the frequency of a variable class plus the frequencies of the classesbelow it iv. Cumulative relative frequency- quantitative 1. (0-1) the relative frequencies plus the relative frequencies of the classes below it c. Ogive: linear version of cumulative histogramsd. Bar graphs- associated with categories (qualitative) e. Pie chart- qualitative, relative frequency chartf. Line graph- x/y causation; change in variable over timeg. X/Y chart- not a continuous sample; change in variable in relation to