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Term frequency–inverse document frequency (TF-IDF):  TF-IDF = Term Frequency (TF) × Inverse document frequency (IDF)         = the frequency of the word `i` in the document `n` × log( ) Where N is the total number of documents and is the number of documents containing word `i`. For example, if there are two documents with three words as vocabulary, the TF-IDF embedding vector for each document is: Based on the above information, TF-IDF weights (1)_________(a. less b. more) frequency words in the given document, while (2)____________(a. less b. more) weights common words in documents.

An economist predicts consumer choice between banana (1), apple (2), and cheese (3) using two input features through the above artificial neural network. Based on the above figure, if the output of the softmax function for each class in the output layer are, 0.1 for banana, 0.2 for apple, and 0.7 for cheese, the consumer will purchase (1)____________ (a. banana, b. apple c. cheese; 2 points). This example is a case of (2) ___________(a. regression, b. binary classification, c. multi-class classification; 2 points). Here, the output of the softmax function in the output layer is the probability of y, where y  

Which one is not true for Latent Dirichlet Allocation (LDA; topic modeling)?

Which one is not a method to select the optimal number of clusters in K-means?

An economist wants to estimate the effect of sentiment in the Reddit post on upvote score (i.e., score) from other users. Accordingly, the economist generates independent variables for sentiment in the post using lexicon-based sentiment analysis. The higher value in the sentiment-independent variables (i.e., sentiment, three_sentiment) means more positive sentiment in a post. Based on the above linear regression results, one unit increase of sentiment in a post ___________ (a. decrease, b. increase) the upvotes score (i.e., score) from other users in Models 2, 3, 4, and 5.

Based on the above plot for the PCA, The (1)___________(a. PC1, b. PC2) captures the largest variance in the sample data. The (2)___________(a. PC1, b. PC2) captures the second largest variance in the sample data. The direction of PC2 is orthogonal to PC1. PC1 and PC2 are (3)___________(a. correlated, b. uncorrelated).

An economist applies LDA to extract three topics and its share for each review from 1,208 Amazon product reviews for non-alcoholic wines because LDA assumes: each document is a mixture of (1)____________ (a.  topics, b. words). and each topic is a mixture of (2)____________ (a. topics, b. words).

Earnings per share (EPS) is $3.00 and shares outstanding are 80,000 and there are no preferred stocks issued by the company. What is net income?  

In the long-term, the concrete frame of a building will expand due to creep and the brick exterior will shorten due to an increase in moisture content.

Consider a system with a main memory access time of 50 ns supported by an L1 cache having a 5 ns access time and a hit rate of 90% and an L2 cache having a 10 ns access time and a hit rate of 80%. What is the average memory access time for a look aside cache? (include units) [Answer1] What is the average memory access time for a look through cache? (include units) [Answer2]