B09 Evaluating Performance Flashcards

Exam Prep

1
Q

The goal of evaluating a ___________ is to have a better understanding of how its performance will _______ to future cases.

A

Classification Model Extrapolate

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2
Q

A ____________ is a table that categorizes predictions according to whether they match the ________.

A

Confusion Matrix Actual Value

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3
Q

The class of interest is known as the ________ class, while all others are known as _______.

A

Positive Negative

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4
Q

The ____________ adjusts accuracy by accounting for the possibility of a correct prediction by chance alone.

A

kappa statistic

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5
Q

Kappa values range from ___ to _____

A

0 (poor) - 1 (good)

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6
Q

Kappa can also be though of as ______

A

Proportion of all instances where the predicted and actual values match.

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7
Q

The _________ is defined as the proportion of positive predictions that are truly positive. A model with high _______ is trustworthy.

A

Precision

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8
Q

The ________is a measure of the completeness of the results. A model with high _______has wide breadth.

A

Recall

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9
Q

The _______ combines precision and recall into a single number using the harmonic mean. It provides a convenient way to compare several models side by side.

A

F-Measure

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10
Q

The _______ of a model (also called the __________) measures the proportion of positive examples that were correctly classified.

A

Sensitivity; True Positive Rate

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11
Q

The __________ of a model (also called the ____________) measures the proportion of negative examples that were correctly classified.

A

Specificity; True Negative Rate

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12
Q

The __________________ is commonly used to examine the trade-off between the detection of true positives, while avoiding the false positives.

A

Receiver Operating Characteristic (ROC) curve

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13
Q

The _______ treats the ROC diagram as a twodimensional square and measures the total area under the ROC curve.

A

Area Under the Curve (AUC)

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14
Q

Most learners present performance measures during training. This is known as the __________ This metric is overly optimistic and cannot reliably measure future performance.

A

Resubstitution error

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15
Q

The _______ method splits data into a ______ and ____ partition. At no time should the performance on the ____ dataset be allowed to influence the model

A

Holdout

Training

Test

Test

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16
Q

Problems with the Holdout Method?

A
  1. Each partition may have a larger or smaller proportion of some classes. This could lead to a class being omitted from the training data (resolved by stratified random sampling).
  2. Some samples may have too many or few difficult cases, easy-to-predict cases, or outliers.
  3. Substantial portions of data must be reserved to test and validate the model.
17
Q

A technique known as _________ is sometimes used to mitigate the problems with the holdout method. It uses the average result from several random holdout samples to evaluate a model’s performance.

A

Repeated Holdout

18
Q

_____ cross-validation randomly divides the data into ___ completely separate random partitions called ____

A

K Fold

K

Folds

19
Q

At the end of K-Fold Cross Validation, the __________ across all the folds is reported.

A

Average performance

20
Q

Some other Cross Validation techniques include:

A

5 Fold Cross Validation

Leave-one-out cross-validation

Random cross-validation

Stratified cross-validation

21
Q

Using sampling with replacement to form training set, _________ presents an alternative to cross-validation

A

bootstrapping

22
Q

Bootstrapping typically uses less data than crossvalidation for training, therefore, its test error will be _________

A

rather pessimistic