How do Individual Contributors Get Stuck?

131. Palindrome Partitioning list all possible partitions and check can cache palindrome

234. Palindrome Linked List reverse half and compare then reverse back 5. Longest Palindromic Substring 9. Palindrome Number 125. Valid Palindrome Character.isLetterOrDigit() StringBuilder.reverse() is mutable 214. Shortest Palindrome brute force LTE small range when compare

Machine Learning Machine Learning Supervised Learning Classification (qualitative) K-NN Logistic Regression Neural Networks error analysis skewed data F1 score = 2PR/(P+R) accuracy precision recall learning curve SVM Kernal Parameters C sigma Regression (quantitative) Linear Regression validation sensitivity compactness Ensemble Learning decrease variance (bagging), bias (boosting), or improve predictions (stacking). The basic motivation of sequential methods is to exploit the dependence between the base learners. The basic motivation of parallel methods

Definitions A type I error occurs when the null hypothesis (H0) is true, but is rejected. Also known as false positive, where positive means rejection of a null hypothesis. A type II error occurs when the null hypothesis is false, but erroneously fails to be rejected. Also called as false negative, where negative refers to retaining a null hypothesis. TPR (True Positive Rate) = # True positives / # positives = Recall = \( TP \over (TP+FN) \)