Machine Learning(26)
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What is "Curse of dimensionality"
In the context of data mining, the curse of dimensionality refers to the fact as the number of features and dimensions in a dataset increases, the amount of data required to accurately represent the distribution of the data increases exponentially, making it difficult to extract useful patterns and relationship from the data. For example, in a dataset with only two features, it may be relatively..
2023.03.08 -
Difference between KNN and LVQ
KNN (K-Nearest Neighbors) and LVQ (Learning Vector Quantization) are both popular machine learning algorithms for classification tasks, but they differ in their approach and methodology. KNN is a non-parametric and lazy learning algorithm, which means that it does not make any assumptions about the underlying distribution of the data and does not learn a model from the training data. Instead, KN..
2023.03.07 -
What is PCA?
PCA stands for Principal Component Analysis. It is a commonly used technique in machine learning and data analysis for reducing the dimensionality of a dataset while preserving as much of the variance in the data as possible. In simple terms, PCA helps to identify patterns and relationships in a dataset by transforming the data into a new coordinate system, where each new dimension (called a pri..
2023.03.07 -
Practice of MLP question
Question : In an MLP which has a single hidden layer with, let's say 10 neurons, and that the network is being trained for 1000 iterations. What is the total number of weights in this MLP? Solution : In an MLP with a single hidden layer and 10 neurons, the total number of weights is the sum of the weights connecting the input layer to the hidden layer and the weights connecting the hidden layer ..
2023.03.07 -
What is ROC?
ROC stands for Receiver Operating Characteristic. It is a graphical representation that illustrates the performance of a binary classification model. The ROC curve plots the true positive rate (TPR) against the false positive rate (FPR) at various threshold settings. The true positive rate (TPR) is also called sensitivity, recall or hit rate and it is the proportion of actual positive cases that..
2023.03.07 -
What is trade-off between sensitivity (or TPR) and specificity (1-FPR)?
In binary classification problems, sensitivity (also called true positive rate or TPR) and specificity (also called true negative rate or TNR) are two common performance metrics used to evaluate the performance of a classification model. Sensitivity measures the proportion of true positives (correctly identified positives) out of all actual positives. It is defined as: TPR = TP / (TP + FN) where..
2023.03.07