ISYE 6501 Midterm 1 QUESTIONS CORRECTLY ANSWERED LATEST UPDAT

ISYE 6501 Midterm 1 QUESTIONS CORRECTLY ANSWERED LATEST UPDATE Support Vector Machine(SVM) is a supervised machine learning algorithm used for? - ANSWER Classification How to split the data if we only have one model? - ANSWER 70% training data, 30% testing data How to split the data if we want to compare models? - ANSWER 70% training, 15% validation and 15% testing When do we need to do scaling in data? - ANSWER When our factors/attributes/dimensions are orders of magnitude different such as income vs. credit score (income is much much larger) Which type of classifier tend to be more overfitting? - ANSWER Soft classifier What is a measure of quality used in linear regression? - ANSWER R-squared or adjusted R-squared: shows how well your model explains the observed data. The higher R-squared, the better the model is expected to perform AIC, BIC: The lower AIC and BIC, the better the model fits Select where each data is categorical a. Education level b. GPA c. Gender d. Temperature - ANSWER a and c What type of data is used in CUSUM? - ANSWER time series data What type of data is used in Exponential Smoothing model? - ANSWER time series data What is GARCH do? - ANSWER variance estimation For KNN and K-means clustering, why is scaling important - ANSWER Otherwise some variables could be associated with more 'weight' reference: What are some approaches to check if outliers are successfully removed - ANSWER e.g., histogram, what are some examples of classification methods we've learned that would fall under the supervised vs. unsupervised algorithms - ANSWER e.g., PCA = unsupervised SVM, KNN = supervised other examples? In the SVM equation, what does the mj variable do? specifically, the mj varaible that's in front of the max { } portion of the equation - ANSWER mj > 1 for more costly errors, and mj <1 for less costly errors Reference: See ISYE-6501 Module 2 Playlist v0822. Video length 5:49; time-stamp 1:53 in KNN, what's the difference between 1-norm and 2-norm? i.e., L1 vs. L2 - ANSWER Different ways of measuring the distance. 1-norm or L1 is the manhattan difference which is based on the difference in terms of x and y. | x1-x2 | + | y1-y2 | where as the L2 is the euclidean distance which is the sqrt((x1- x2)^2 + (y1-y2)^2) what does it mean if k = 1 in the context of knn - ANSWER it means you'll predict a unknown data point as the same class as its single closest neighbor is k-means algorithm heuristic? yes or no? and if yes, what does it mean? - ANSWER yes. heuristic = "fast, good, but not guaranteed to find absolute best solution" Reference: M4L3 4:22/5:27 time stamp if there are 100 samples and we've decided to do a 5 fold crossvalidation, how many training and t