AWS Certified Machine Learning Specialty · Free Practice Question Easy
Question 6
A retail organization wants to forecast the sales of its flagship products for the upcoming festive season. They have the last 5 years of sales data for these products.
As an ML specialist, which algorithm would you use to implement the forecasting solution?
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A
Semantic Segmentation
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B
Random Cut Forest
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C
Linear Learner
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D
Latent Dirichlet Allocation (LDA)
Reveal correct answer
Correct answer: C
Explanation
Correct option:
Linear Learner
Linear models are supervised learning algorithms used for solving either classification or regression problems. For input, you give the model labeled examples (x, y). x is a high-dimensional vector and y is a numeric label. For binary classification problems, the label must be either 0 or 1. For multiclass classification problems, the labels must be from 0 to num_classes - 1. For regression problems, y is a real number. The algorithm learns a linear function, or, for classification problems, a linear threshold function, and maps a vector x to an approximation of the label y.
The given use case is for a regression problem that can be easily solved using the Linear Learner algorithm.
Incorrect options:
Latent Dirichlet Allocation (LDA) - The Amazon SageMaker Latent Dirichlet Allocation (LDA) algorithm is an unsupervised learning algorithm that attempts to describe a set of observations as a mixture of distinct categories. LDA is most commonly used to discover a user-specified number of topics shared by documents within a text corpus. Here each observation is a document, the features are the presence (or occurrence count) of each word, and the categories are the topics. Since the method is unsupervised, the topics are not specified up front, and are not guaranteed to align with how a human may naturally categorize documents. The topics are learned as a probability distribution over the words that occur in each document. Each document, in turn, is described as a mixture of topics.
LDA is used for topic modeling, so it is not the right fit for the given use case.
Semantic Segmentation - The SageMaker semantic segmentation algorithm provides a fine-grained, pixel-level approach to developing computer vision applications. It tags every pixel in an image with a class label from a predefined set of classes. Tagging is fundamental for understanding scenes, which is critical to an increasing number of computer vision applications, such as self-driving vehicles, medical imaging diagnostics, and robot sensing.
Semantic Segmentation is used for image analysis, so it is not the right fit for the given use case.
Random Cut Forest - Amazon SageMaker Random Cut Forest (RCF) is an unsupervised algorithm for detecting anomalous data points within a data set. These are observations which diverge from otherwise well-structured or patterned data. Anomalies can manifest as unexpected spikes in time series data, breaks in periodicity, or unclassifiable data points. They are easy to describe in that, when viewed in a plot, they are often easily distinguishable from the "regular" data. Including these anomalies in a data set can drastically increase the complexity of a machine learning task since the "regular" data can often be described with a simple model.
Random Cut Forest is used to detect outliers, so it is not the right fit for the given use case.
Reference:
https://docs.aws.amazon.com/sagemaker/latest/dg/linear-learner.html
Discussion
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