Adjustment Computations - Charles D. Ghilani

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Résumé :

Provides Comprehensive, Up-to-Date Guidance on Spatial Data Accuracy

As modern surveying, mapping, and geospatial technologies continue to evolve, the need for precise data adjustment and error analysis has never been greater. Adjustment Computations: Spatial Data Analysis, Seventh Edition, remains the definitive guide to understanding, applying, and mastering least squares and related techniques that ensure the accuracy of spatial datasets.

This updated edition integrates advances in spatial technologies, with new chapters covering laser scanning, point cloud processing, and parametric model estimation. Updated discussions of ASPRS standards, NSRS updates, and current computational tools reflect the latest professional practices and technologies. The text maintains its clear, pedagogical structure with concise chapters, worked examples, and practical software applications. Providing the analytical tools to deliver high-quality spatial data for diverse applications, this book:

• Includes coverage of laser scanning and its errors, point cloud shape fitting, GNSS networks, coordinate transformations, and parametric modeling
• Incorporates updated standards from ASPRS and the National Spatial Reference System (NSRS)
• Provides access to companion software, MathCAD worksheets, and video lessons for hands-on problem solving
• Balances rigorous mathematics with accessible explanations and real-world surveying applications
• Features real-world case studies of infrastructure documentation, construction, and environmental monitoring

Ideal for undergraduate and graduate courses in surveying, geomatics, and geospatial analysis, Adjustment Computations: Spatial Data Analysis, Seventh Edition, supports curricula in civil engineering, geosciences, and GIS programs. It is also a useful reference for professional surveyors and geospatial analysts seeking to enhance data accuracy and reliability....

Biographie:

Preface xvii

Acknowledgments xxiii

About the Companion Website xxv

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 19

2.7 Additional Definitions 19

2.8 Alternative Formulas for Determining Variance 22

2.9 Numerical Examples 25

2.10 Root Mean Square Error and Mapping Standards 29

2.11 Derivation of the Sample Variance (Bessel's Correction) 32

2.12 Software 33

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 49

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 64

4.4 Testing the Validity of the Confidence Interval 67

4.5 Selecting a Sample Size 67

4.6 Confidence Interval for a Population Variance 69

4.7 Confidence Interval for the Ratio of Two Population Variances 70

4.8 Software 73

Problems 75

5 Statistical Testing 81

5.1 Hypothesis Testing 81

5.2 Systematic Development of a Test 84

5.3 Test of Hypothesis for the Population Mean 86

5.4 Test of Hypothesis for the Population Variance 88

5.5 Test of Hypothesis for the Ratio of Two Population Variances 91

5.6 Using Software 94

Problems 95

6 Propagation of Random Errors in Indirectly Measured Quantities 99

6.1 Basic Error Propagation Equation 99

6.2 Frequently Encountered Specific Functions 104

6.3 Numerical Examples 105

6.4 Software 109

6.5 Conclusions 111

Problems 111

Practical Exercises 114

7 Error Propagation in Angle and Distance Observations 115

7.1 Introduction 115

7.2 Error Sources in Horizontal Angles 116

7.3 Reading Errors 116

7.4 Pointing Errors 118

7.5 Estimated Pointing and Reading Errors with Total Stations 119

7.6 Target Centering Errors 120

7.7 Instrument Centering Errors 122

7.8 Effects of Leveling Errors in Angle Observations 126

7.9 Numerical Example of Combined Error Propagation in a Single Horizontal Angle 128

7.10 Using Estimated Errors to Check Angular Misclosure in a Traverse 130

7.11 Errors in Astronomical Observations for Azimuth 132

7.12 Errors in Electronic Distance Observations 137

7.13 Centering Errors When Using Range Poles 138

7.14 Software 139

Problems 140

Programming Problems 143

8 Error Propagation in Traverse Surveys 145

8.1 Introduction 145

8.2 Derivation of Estimated Error in Latitude and Departure 146

8.3 Derivation of Estimated Standard Errors in Course Azimuths 148

8.4 Computing and Analyzing Polygon Traverse Misclosure Errors 148

8.5 Computing and A...

Sommaire:

CHARLES D. GHILANI is a Professor Emeritus of Engineering at Pennsylvania State University and an award-winning authority on surveying and geodesy.

DIMITRIOS BOLKAS is an Associate Professor of Surveying Engineering at Pennsylvania State University, specializing in laser scanning and GNSS networks.

MICHAEL J. OLSEN is the CH2M Hill Professor of Civil Engineering at Oregon State University and a leader in geomatics and 3D laser scanning applications....