Question: Consider a document-term matrix, where tfij is the frequency of the ith word (term) in the jth document and m is the number of documents.

Consider a document-term matrix, where tfij is the frequency of the ith word (term) in the jth document and m is the number of documents. Consider the variable transformation that is defined by

where dfi is the number of documents in which the ith term appears and is known as the document frequency of the term. This transformation is known as the inverse document frequency transformation.
(a) What is the effect of this transformation if a term occurs in one document? In every document?
(b) What might be the purpose of this transformation?

7m 2 10

Step by Step Solution

★★★★★

3.40 Rating (163 Votes )

There are 3 Steps involved in it

1 Expert Approved Answer

Step: 1 Unlock

a Terms that occur in every document have 0 weight while thos... View full answer

Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock

Step: 3 Unlock

Document Format (1 attachment)

908-M-S-D-A (8572).docx

120 KBs Word File

Students Have Also Explored These Related Statistics Questions!

The vibrational contribution to the molar heat capacity of a gas of nonlinear molecules is given in statistical mechanics by the formula i=1 " style="" class="fr-fic fr-dib"> where u i =...

Approximate the median of the frequency distribution in Problem 2. Square Footage .... Frequency 0-499 .......... 5 500-999 ........ 17 1000-1499 ....... 36 1500-1999 ....... 121 2000-2499 ...... 119...

Approximate the median of the frequency distribution in Problem 3. Temperature (F) ....Frequency 61-64 ......... 31 65-67 ......... 67 68-69 .......198 70 .........195 71-72 ........120 73-76...

Exercise 3.25 (Document-Term Matrices): Suppose we have an mn documentterm matrix A where each row corresponds to a document and has been normalized to length one. Define the "similarity" between two...

MATHEMATICS FOR MACHINE LEARNING Marc Peter Deisenroth A. Aldo Faisal Cheng Soon Ong Contents Foreword 1 Part I Mathematical Foundations 9 1 Introduction and Motivation 11 1.1 Finding Words for...

PROBLEM 2 This exercise is about topic analysis. A topic is a latent variable that represents or summarizes important concepts of a text, such as its meaning or main ideas. A topic is made up of...

Make sense of the thoughts of static and dynamic chains, giving an illustration of a circumstance in which they contrast (for example reference to some unacceptable one would get to the wrong...

Developments in Technology Light is incident from air on the end face of a multimode optical fibre at angle of incidence as shown below. n n 1 2 The refractive indices of the core and cladding are...

I have to do an accounting assignment. I have attached the instructions, the questions, and pdf's containing the information requested for the questions. Company Estimates & Opinions Sanmina Corp...

7 Writing in the Workplace If writing must be a precise form of communication, it should be treated like a precision instrument. It should be sharpened, and it should not be used carelessly. Theodore...

Use the Errors in the Trapezoidal Rule and Simpson's Rule Theorem to estimate the errors in approximating the integral, with n 4, using the Trapezoidal Rule and Simpson's Rule, (6x + 3) dx (a) the...

You are the auditor in charge of the Strong Developers Ltd audit engagement. You are preparing for the upcoming audit of Strong Developers for the year ended December 31, 2020. Strong Builders is a...

11. Discuss the basic accounting problem that arises in handling each of the following situations. a. Assets purchased by issuance of ordinary shares. b. Acquisition of plant assets by grant. c....

2. Togetherness Are good grades in high school associated with family togetherness? A random sample of 142 high school students was asked how many meals per week their families ate together. Their...

Use the churn data set at the book series website for the following exercises. Make sure that the correlated variables have been accounted for. Construct a gains chart for the default CART model....

Use the churn data set at the book series website for the following exercises. Make sure that the correlated variables have been accounted for. Construct a lift chart for the default CART model. What...

Use the churn data set at the book series website for the following exercises. Make sure that the correlated variables have been accounted for. Perform a cost/benefit analysis for the CART model with...

) An 18-month 100 zero-coupon bond sells for 93. A 3-year 100 zero-coupon bond sells for 84. Using semi-annual compounding (i.e. every 6 months), find the forward rate between 18-months and 36-...

5. Binary erasure channel (15 points). A binary erasure channel has binary input X e {0, 1} and ternary output Y E {0, 1, 2} (see the probability transition diagram below). The erasure, represented...

Please show how to retrieve answers with formula. 11. How many monthly payments remain to be paid on an 8% mortgage with a 30-year amortization and monthly payments of $733.76, when the balance...