Object Detection and Classification

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What is the definition of similarity used to compare two boxes?

Intersection over Union (IoU) (correct)

Jaccard Distance

Jaccard Similarity

Intersection over Difference

What is the primary condition for a prediction P to be considered a true positive?

P and G have the same scoring value

G was not matched to a higher scoring prediction P'

P's box has sufficient similarity to G's box

P and G have the same category label (correct)

What IoU value is considered 'almost perfect'?

IoU > 0.3

IoU > 0.7

IoU > 0.9 (correct)

IoU > 0.5

What is the class score of 'cat' in the given model?

0.9 Signup and view all the answers

What is the purpose of ranking by score in defining matches?

To break ties between multiple predictions Signup and view all the answers

What is a prediction P matched to if it satisfies conditions (1-3)?

A ground truth G Signup and view all the answers

What is the input size of the fully connected layer?

4096 to 1000 Signup and view all the answers

What type of problem is localization treated as in this model?

Regression Signup and view all the answers

What strategy is rarely used in practice to define matches?

Optimal bipartite matching Signup and view all the answers

What is the shape of the correct box in this model?

(x', y', w', h') Signup and view all the answers

What is the loss function composed of in this model?

Lcls + Lreg Signup and view all the answers

What is the purpose of the softmax function in this model?

To calculate the class scores Signup and view all the answers

What is the most popular metric used in evaluation?

Average precision Signup and view all the answers

What is the purpose of having multiple definitions of AP?

To accommodate different dataset requirements Signup and view all the answers

Why did early datasets use an IoU threshold of 0.5?

Because the detection problem was too hard Signup and view all the answers

What is the goal of achieving an AP of 1?

To achieve perfect recall and precision Signup and view all the answers

Why are larger datasets extending to multiple IoU thresholds?

Because the detection problem is established and there's good progress Signup and view all the answers

What is the significance of AP being a generic metric?

Doing well on AP should be good for many applications Signup and view all the answers

What is the main motivation behind defining Average Precision (AP)?

To have a single number that communicates the model's performance on the dataset Signup and view all the answers

What does Precision@s measure?

The fraction of detections that are correct with score >= s Signup and view all the answers

What is the purpose of the Precision-Recall curve?

To visualize the trade-off between precision and recall Signup and view all the answers

What is the range of Average Precision (AP)?

0 to 1 Signup and view all the answers

What is Recall@s measuring?

The fraction of ground-truth objects detected with score >= s Signup and view all the answers

How is Average Precision (AP) calculated?

The area under the Precision-Recall curve Signup and view all the answers

What is AP[ℂ] an abbreviation for?

Average Precision of multiple categories Signup and view all the answers

What is AP[C, IoU] an abbreviation for?

Average Precision of Category C with IoU threshold Signup and view all the answers

Object Detection and Classification

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