30 Questions
What is the primary challenge in producing maps?
Balancing precision and accuracy
Why is it essential to plan an accuracy assessment ahead of time?
To ensure the accuracy of the map analysis
What is the primary goal of collecting reference data?
To validate the accuracy of the classified map
What is the key characteristic of a random sampling design?
Points are randomly distributed throughout the study area
What is the primary benefit of using a systematic sampling design?
It provides complete and regular coverage of the study area
What factor influences the size of the sampling locations?
The spatial resolution of the data set
What type of error occurs when a site is classified as a reference site, but it was not actually a reference site?
Commission Error
If an urban area has 2 incorrectly classified sites out of a total of 25 classified sites, what is the Commission Error?
8%
What type of error occurs when a reference site is not included in the classified map?
Omission Error
If a forest area has 10 reference sites, but 2 of them were incorrectly classified, what is the Omission Error?
20%
What perspective does Producer’s Accuracy represent?
The mapmaker
If a water area has 5 incorrectly classified sites out of a total of 30 classified sites, what is the Commission Error?
16%
What is the formula to calculate the overall accuracy?
Total number of correctly classified sites / Total number of reference sites
What is the relationship between error and accuracy?
Error + accuracy = 100%
What type of error occurs when a reference site is left out of the correct class in the classified map?
Error of Omission
How is the error of omission calculated?
By reviewing the reference sites for incorrect classifications
What is the perspective of the Producer's Accuracy?
From the point of view of the mapmaker
What happens when an error of omission occurs in one category?
It is counted as an error of commission in another category
What is the Producer's Accuracy a measure of?
The number of correctly classified reference sites divided by the total number of reference sites
What is the relationship between the Producer's Accuracy and the Omission Error?
The Producer's Accuracy is the difference between 100% and the Omission Error
What is the User's Accuracy a measure of?
The reliability of the map from the user's point of view
What is the relationship between the User's Accuracy and the Commission Error?
The User's Accuracy is the difference between 100% and the Commission Error
If a class has a Producer's Accuracy of 80%, what is the Omission Error?
20%
If a class has a User's Accuracy of 90%, what is the Commission Error?
10%
What proportion of the Water reference sites were correctly identified in the classified imagery?
63.64%
What do the off-diagonal elements of the error matrix represent?
Areas that were not classified correctly
What is the primary benefit of calculating overall accuracy?
It provides basic information about the proportion of correctly mapped reference sites
What is the purpose of examining the off-diagonal elements of the error matrix?
To identify areas where the most errors occurred in the classification
How many reference sites were correctly classified out of a total of 95 sites?
74
What is the primary purpose of the error matrix in remote sensing classification?
To improve the thematic accuracy of classification
Learn about the steps involved in conducting an accuracy assessment for map production, including developing a sampling system, collecting reference data, and computing accuracy metrics.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
