Questions tagged [decision-tree]
43 questions
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In information theory, why is the entropy measured in units of bits?
In information theory, we have the quantity "information".
Suppose we have some discrete random variable $X$, that can take values $\{{a,b,c\}}$ with corresponding probability distribution $\{{\frac{1}{2},\frac{1}{4},\frac{1}{4}\}}$. Then,…
Data
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Classify/Distinguish between 8008 binary grids, with 13 queries
I have $8008$ binary grids of size $6 \times 10$ (they are all grids with the property described below), which I want to distinguish between with at most $13$ queries. A query will determine if the cell $A_{i,j}$ of a grid is $0$ or $1$.
The grids…
spyr03
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What do Arora and Barak mean by $x|_S$ in their definition of certificate complexity?
I am having much trouble understanding the following definition (of certificate complexity - for decision trees) from Arora and Barak's book Computational Complexity: A Modern Approach. Perhaps there is a typo in it:
Definition 12.3 (page 262). Let…
Andrew Kelley
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3
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What is the main difference between binary decision tree and binary decision diagram(BDD)?
What is the main difference between binary decision tree and binary decision diagram(BDD)? From what I can tell I only understand that a binary decision diagram is a more compact representation because it eliminates nodes that have both edges…
Teodorico Levoff
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3
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Expressivity of Polysize Decision Trees
A binary decision tree (DT) is a binary tree whose internal nodes are labelled by boolean variables (with repetitions), and whose leaves are labelled either $0$ or $1$. The size of a decision tree is the number of branches (or equivalently the…
integrator
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Basic exercises on decision trees
I am a pure math person doing some ML self-study and I am pretty lost.
I am trying to solve the following exercises on decision trees:
Exercise 1. Consider the following training set where
$X_1,X_2,X_3,X_4$ are the attributes and $Y$ is the class…
mat95
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how does the shap algorithm work in polynomial time?
I'm trying to understand how the shap algorithm calculates in polynomial time an estimation to the feature attribution function that satisfies the shapely value attributes (specifically for tree based models!).
A simplified version of the feature…
ihadanny
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3
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Finding maximum takes at least $\lceil n/2 \rceil$ comparisons
We are given an array $A$ with $n$ elements, $n \in \mathbb{N}$ and all elements are in the set $\{1,2,3, \cdots, n \}$.
I want to prove that finding the maximum in $A$ (that is, outputting the index at which the maximum is found in $A$) takes at…
QWE
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decision trees and numeric attributes
I have been reading a book about Decision Trees and it caught my attention the following part:
In case of numeric attributes, decision trees can be geometrically
interpreted as a collection of hyperplanes, each orthogonal to one of
the axes
I…
Layla
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Avoiding collisions in space and time
Say I have an image, represented as a 2D array of pixel values. Also, say I have a set of points on that image where each has a current (x, y) position and a Destination (x, y) associated with it. I want to find a path for each point to its…
Michael O'Brien
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What machine learning training algorithm to use for this kind of string dataset?
I am working on a project where I have to train the following data-set using machine learning algorithm. One of my friend suggested decision tree, but I have never seen a situation where independent variable has more than 100 values in decision…
minigeek
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2
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Decision Tree Learning Deviation - Russell and Norvig
I am working through the Russell and Norvig AI book and came across the following on the top of page 706.
The section concerns Decision Tree pruning and testing a given attribute against the null hypothesis. The example at hand deals with a binary…
ClownInTheMoon
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Decision tree for searching element in sorted-array
Given the problem of having a sorted array $A$, an element $x$ to be searched for in the array $ A $, what is a lower-bound on the process of finding $x$ in $A$?
The answer is $ \Omega(\log n) $ because I was told that $ n $ is the number of leaves…
flamel12
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Decision Tree for searching an element in an n*n matrix
I just learnt decision tree concept in class. I have a question for homework. It says to prove that for searching an element in n*n matrix the lower bound is logn and prove it using decision tree.
My question here is using comparison based model,…
Shahrukh
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Attribute Selection for minimum number of clusters
I have a table consisting of some headers $P, Q, R, S$ (shown in blue in Table 1). According to the headers, the column $T$ is populated using some predefined logic.
Now, any of the headers $P,Q,R,S$ may be wildcarded to match all values.
The aim to…
Niloy Saha
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