Read more
The definitive guide to bringing accuracy to measurement, updated and supplemented
Adjustment Computations is the classic textbook for spatial information analysis and adjustment computations, providing clear, easy-to-understand instruction backed by real-world practicality. From the basic terms and fundamentals of errors to specific adjustment computations and spatial information analysis, this book covers the methodologies and tools that bring accuracy to surveying, GNSS, GIS, and other spatial technologies. Broad in scope yet rich in detail, the discussion avoids overly-complex theory in favor of practical techniques for students and professionals. This new sixth edition has been updated to align with the latest developments in this rapidly expanding field, and includes new video lessons and updated problems, including worked problems in STATS, MATRIX, ADJUST, and MathCAD.
All measurement produces some amount of error; whether from human mistakes, instrumentation inaccuracy, or environmental features, these errors must be accounted and adjusted for when accuracy is critical. This book describes how errors are identified, analyzed, measured, and corrected, with a focus on least squares adjustment--the most rigorous methodology available.
* Apply industry-standard methodologies to error analysis and adjustment
* Translate your skills to the real-world with instruction focused on the practical
* Master the fundamentals as well as specific computations and analysis
* Strengthen your understanding of critical topics on the Fundamentals in Surveying Licensing Exam
As spatial technologies expand in both use and capability, so does our need for professionals who understand how to check and adjust for errors in spatial data. Conceptual knowledge is one thing, but practical skills are what counts when accuracy is at stake; Adjustment Computations provides the real-world training you need to identify, analyze, and correct for potentially crucial errors.
List of contents
PREFACE xv
ACKNOWLEDGMENTS xix
1 Introduction 1
1.1 Introduction / 1
1.2 Direct and Indirect Measurements / 2
1.3 Measurement Error Sources / 2
1.4 Definitions / 3
1.5 Precision versus Accuracy / 4
1.6 Redundant Observations in Surveying and Their Adjustment / 7
1.7 Advantages of Least Squares Adjustment / 8
1.8 Overview of the Book / 10
Problems / 10
2 Observations and Their Analysis 13
2.1 Introduction / 13
2.2 Sample versus Population / 13
2.3 Range and Median / 14
2.4 Graphical Representation of Data / 15
2.5 Numerical Methods of Describing Data / 18
2.6 Measures of Central Tendency / 18
2.7 Additional Definitions / 19
2.8 Alternative Formula for Determining Variance / 22
2.9 Numerical Examples / 24
2.10 Root Mean Square Error and Mapping Standards / 28
2.11 Derivation of the Sample Variance (Bessel's Correction) / 31
2.12 Software / 32
Problems / 34
Practical Exercises / 37
3 Random Error Theory 39
3.1 Introduction / 39
3.2 Theory of Probability / 39
3.3 Properties of the Normal Distribution Curve / 42
3.4 Standard Normal Distribution Function / 44
3.5 Probability of the Standard Error / 47
3.6 Uses for Percent Errors / 50
3.7 Practical Examples / 50
Problems / 53
Programming Problems / 55
4 Confidence Intervals 57
4.1 Introduction / 57
4.2 Distributions Used in Sampling Theory / 59
4.3 Confidence Interval for the Mean: t Statistic / 63
4.4 Testing the Validity of the Confidence Interval / 66
4.5 Selecting a Sample Size / 67
4.6 Confidence Interval for a Population Variance / 68
4.7 Confidence Interval for the Ratio of Two Population Variances / 70
4.8 Software / 72
Problems / 75
5 Statistical Testing 79
5.1 Hypothesis Testing / 79
5.2 Systematic Development of a Test / 82
5.3 Test of Hypothesis for the Population Mean / 84
5.4 Test of Hypothesis for the Population Variance / 85
5.5 Test of Hypothesis for the Ratio of Two Population Variances / 89
5.6 Software / 92
Problems / 93
6 Propagation of Random Errors in Indirectly Measured Quantities 97
6.1 Basic Error Propagation Equation / 97
6.2 Frequently Encountered Specific Functions / 102
6.3 Numerical Examples / 103
6.4 Software / 107
6.5 Conclusions / 109
Problems / 109
Practical Exercises / 112
7 Error Propagation in Angle and Distance Observations 113
7.1 Introduction / 113
7.2 Error Sources in Horizontal Angles / 113
7.3 Reading Errors / 114
7.4 Pointing Errors / 116
7.5 Estimated Pointing and Reading Errors with Total Stations / 117
7.6 Target-Centering Errors / 118
7.7 Instrument Centering Errors / 120
7.8 Effects of Leveling Errors in Angle Observations / 123
7.9 Numerical Example of Combined Error Propagation in a Single Horizontal Angle / 126
7.10 Using Estimated Errors to Check Angular Misclosure in a Traverse / 127
7.11 Errors in Astronomical Observations for Azimuth / 130
7.12 Errors in Electronic Distance Observations / 135
7.13 Centering Errors When Using Range Poles / 136
7.14 Software / 137
Problems / 138
Programming Problems / 141
8 Er
About the author
DR. CHARLES D. GHILANI is a Professor Emeritus of Engineering. He taught in the B.S. Surveying Engineering and A.S. Surveying Technology programs at Pennsylvania State University. He holds a Ph.D. and M.S. in Civil and Environmental Engineering from the University of Wisconsin-Madison, and a B.S. degree in mathematics and education from the University of Wisconsin-Milwaukee. He is an honorary member of the Pennsylvania Society of Land Surveyors (P.S.L.S.), the president of the American Association for Geodetic Surveying, and the editor of
Surveying and Land Information Science. He has received the Milton S. Eisenhower Distinguished Teaching Award in 2013, and the 2017 Surveying and Geomatics Educator's Society Educator Award.
Summary
The definitive guide to bringing accuracy to measurement, updated and supplemented Adjustment Computations is the classic textbook for spatial information analysis and adjustment computations, providing clear, easy-to-understand instruction backed by real-world practicality.
