Exam (elaborations)
ISYE 6501 - Quiz 1 Questions and Answers.
- Course
- Institution
ISYE 6501 - Quiz 1 Questions and Answers.
[Show more]
Seller
Follow
Content preview
ISYE 6501 - Quiz 1Questions and Answers
Denning [Date] [Course title]
,Classification: What is it? What are the types? - Correct Answers:s :Classification groups things into
discrete categories.
The types of classification are hard classification and soft classification.
Hard Classification vs Soft Classification - Correct Answers:s :Hard: 100% separation between groups
Soft: minimize misclassifications where possible
Margin vs Accuracy Trade Off - Correct Answers:s :A small margin for error reduces your chances of
misclassifying known data points but increases your chances of misclassifying unknown data points.
A large margin for error increases your chances of misclassifying known data points but decreases your
chances of misclassifying unknown data points.
Making trade off decisions is based on what the cost is for a false-positive and false-negative in a given
business problem.
Support Vector Machine (SVM): How do they work and what are their objectives? - Correct
Answers:s :SVM a classifier that draws a line that best separates groups of data points. It does this by
creating two outer lines that represent the margin for error and a middle line that is the classifier.
Objectives:
1. All data points are categorized correctly (accuracy)
2. Maximize the gap between the two outer lines (margin)
SVM Hard Classifier: What are the parts and what do they represent? - Correct Answers:s :"Subject to all
points being accurate, we seek to maximize margin of error"
The sum of coefficents x variables x y must be greater than or equal to 1 in order order to maintain
accuracy. y is the response variable (-1 or 1), so the classifier must produce a prediction that is the same
sign as the response variable in order for the equation to be true. This part of the equation ensure
accuracy.
, We seek to minimize the sum of coefficients squared since that is the denominator of the margin
calculation (2 / sqrt(sum of coefficents)^2). Therefore, minimizing the sum of coefficients squared
maximizes the margin of our equation. This part of the equation maximizes margin.
SVM Soft Classifier: What are the parts and what do they represent? - Correct Answers:s :"Minimize the
sum of total error and square coefficients" We seek to minimize both in order to minimize error while
maximizing margin.
Max(0 , 1 - the sum of coefficients x variables x y) is the portion of the equation that measures error. Any
misclassifications will produce a sum of coefficients x variables x y value that is negative which will be
added to the total error. This part of the equation ensure accuracy.
Like in hard classification, we seek to minimize the sum of coefficients squared in order to maximize
margin. This part of the equation maximizes margin.
Unlike hard classification, we have the variable lambda that is multiplied with margin which can act as a
"lever" for what we want to prioritize.
Lambda in SVM Soft Classifier - Correct Answers:s :Lambda is the parameter we can set to control the
trade off between margin and accuracy.
Increasing lambda increases the emphasis the model has on margin.
Decreasing lambda increases the emphasis the model has on accuracy.
How do you add business context to build the optimal SVM? - Correct Answers:s :You can add the cost
of a misclassification to your model by weighting the a0 variable (intercept).
Ex. If a bad loan (-1) is twice as costly as a good loan (1) you can weight the a0 variable as 2/3*(a0-1) +
1/3(a0+1)
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller NETEXPERT. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $12.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
79223 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now