Recent questions tagged goclasses-da-course

1 1 vote
0 0 answers
279
279 views
Construct a matrix A with each of the following properties, or explain why no such matrix exists:(a) The column space of A contains the vector (0, 2, 1),and the null spac...
14 14 votes
4 4 answers
1.1k
1.1k views
Say that $S: \mathbb{R}^{2} \rightarrow \mathbb{R}^{3}$ and $T: \mathbb{R}^{3} \rightarrow \mathbb{R}^{4}$ are linear transformations. Which of the following must be true...
5 5 votes
2 2 answers
779
779 views
Let $T: \mathbf{R}^{n} \rightarrow \mathbf{R}^{m}$ be a linear transformation with matrix $A$.How many rows and columns does $A$ have?If $x$ is in $\mathrm{R}^{n}$, then ...
6 6 votes
3 3 answers
654
654 views
Circle $\mathbf{T}$ if the statement is always true, and circle $\mathbf{F}$ otherwise.A. $\mathbf{T} \quad \mathbf{F} \quad$ If $T: \mathbf{R}^{n} \rightarrow \mathbf{R}...
7 7 votes
2 2 answers
848
848 views
Consider $T: \mathbf{R}^{3} \rightarrow \mathbf{R}^{4}$ given by$$T(x, y, z)=(x, x+z, 3 x-4 y+z, x) .$$Is $T$ one-to-one? Justify your answer.
6 6 votes
2 2 answers
568
568 views
Which of the following statements are true?The transformation $T(x, y, z)=(y-1,4 x+z, x)$ is an onto linear transformation.Let $A$ be a $3 \times 4$ matrix. Then, the tra...
6 6 votes
2 2 answers
542
542 views
Which of the following is not a condition for a transformation $T: \mathbf{R}^{n} \rightarrow \mathbf{R}^{m}$ with standard matrix $A$ to be onto?The columns of $A$ span ...
4 4 votes
3 3 answers
537
537 views
If $T: \mathbf{R}^{n} \rightarrow \mathbf{R}^{m}$ is onto, what can we say about the relative sizes of $n$ and $m$ ?
4 4 votes
4 4 answers
653
653 views
Let $T: \mathbb{R}^{3} \rightarrow \mathbb{R}^{3}$ be the matrix mapping with corresponding matrix$$\mathbf{A}=\left[\begin{array}{ccc}1 & 2 & -1 \\-3 & -4 & 2 \\5 & 2 & ...
3 3 votes
2 2 answers
529
529 views
Let $\mathrm{T}_{\mathrm{A}}: \mathbb{R}^{4} \rightarrow \mathbb{R}^{3}$ be the matrix mapping with corresponding matrix$$\mathbf{A}=\left[\begin{array}{cccc}1 & 2 & -1 &...
10 10 votes
2 2 answers
583
583 views
If $\mathrm{T}_{\mathbf{A}}: \mathbb{R}^{n} \rightarrow \mathbb{R}^{m}$ is a matrix mapping corresponding to $\mathbf{A} \in M_{m \times n}$ and $n<m$ then $T_A$ cannot b...
5 5 votes
1 1 answer
802
802 views
A vector mapping $\mathrm{T}: \mathbb{R}^{n} \rightarrow \mathbb{R}^{m}$ is said to be onto if for each $\mathbf{b} \in \mathbb{R}^{m}$ there is at least one $\mathbf{x} ...
10 10 votes
2 2 answers
452
452 views
Let $T: \mathbb{R}^{n} \rightarrow \mathbb{R}^{m}$ be a linear transformation and let $A$ be the standard matrix for $T$. Then:a. $T$ maps $\mathbb{R}^{n}$ onto $\mathbb{...
8 8 votes
2 2 answers
496
496 views
I.A vector mapping $\mathrm{T}: \mathbb{R}^{n} \rightarrow \mathbb{R}^{m}$ is said to be one-to-one if for each $\mathbf{b} \in \operatorname{Range}(\mathrm{T})$ there ex...
5 5 votes
2 2 answers
590
590 views
Let $\mathrm{T}_{\mathrm{A}}: \mathbb{R}^{2} \rightarrow \mathbb{R}^{3}$ be the matrix mapping with corresponding matrix$$\mathbf{A}=\left[\begin{array}{cc}1 & 4 \\-3 & 2...
6 6 votes
2 2 answers
447
447 views
Suppose $T: \mathbf{R}^{3} \rightarrow \mathbf{R}^{3}$ is a linear transformation whose range is a plane, and suppose$$T\left(\begin{array}{l}0 \\1 \\0\end{array}\right)=...
4 4 votes
1 1 answer
394
394 views
Let $\mathrm{T}_{\mathrm{A}}: \mathbb{R}^{4} \rightarrow \mathbb{R}^{3}$ be the matrix mapping with matrix$$\mathbf{A}=\left[\begin{array}{cccc}3 & -2 & 6 & 4 \\-1 & 0 & ...
4 4 votes
1 1 answer
350
350 views
Let $\mathrm{T}_{\mathrm{A}}: \mathbb{R}^{2} \rightarrow \mathbb{R}^{3}$ be the matrix mapping with matrix$$\mathbf{A}=\left[\begin{array}{cc}1 & 0 \\3 & -1 \\2 & 0\end{a...
6 6 votes
1 1 answer
526
526 views
Let $T: \mathbf{R}^{\mathbf{2}} \rightarrow \mathbf{R}^{2}$ be the linear transformation satisfying$$T\binom{1}{0}=\binom{1}{2} \quad \text { and } \quad T\binom{1}{1}=\b...
0 0 votes
1 1 answer
466
466 views
Compute the Linear Discriminant projection for the following twodimensional dataset.- Samples for class $\omega_1: \mathbf{X}_1=\left(\mathrm{x}_1, \mathbf{x}_2\right)=\{...
2 2 votes
1 1 answer
382
382 views
Which of the following are true about two-class Gaussiam discriminant analysis? Assume you have estimated the parameters $\hat{\mu}_{\mathrm{C}}, \hat{\Sigma}_{\mathrm{C}...
0 0 votes
0 0 answers
221
221 views
Which statements are true of Gaussian discriminant analysis for two-class classification, specifically quadratic discrimimemt analysis (QDA) and linear discriminant analy...
0 0 votes
2 2 answers
395
395 views
You want to train a dog identifier with Gaussian discriminant analysis. Your classifier takes an image vector as its input and outputs 1 if it thinks it is a dog, and 0 o...
0 0 votes
0 0 answers
237
237 views
Which one of the following statements on initialization is false?The variances of layer outputs remain unchanged during training when Xavier initialization is used.Initia...
0 0 votes
1 1 answer
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243 views
Which of the options are correct, select all that apply ?Maximum value of local gradient when sigmoid is used as an activation function is 0.5.Minimum value of local grad...
0 0 votes
1 1 answer
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230 views
Which of the options are correct, select all that apply?You are solving a binary classification task, and the final two layers in your network are a ReLU activation follo...
0 0 votes
0 0 answers
228
228 views
A NEural nnetwork has many layers, with the final two being $X$(with 4 nodes) and $Y$(with one node). Four weights $\{ w_1 = 0.1, w_2 = -0.5, w_3 = 0.8, w_4 = 0.6\}$. Con...
0 0 votes
0 0 answers
204
204 views
Consider the neural network below. Note that:$x$, a scalar, is the input. $a_4$, also a scalar, is the output.Each $a_i$, value is the final output for neuron $i$ in the ...
0 0 votes
0 0 answers
212
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Below is a neural network with weights $a,b,c, d,e, f$. The inputs are $x_1$ and $x_2$. The first hidden layer computes $r_1 = max(c \cdot x_1 + e \cdot x_2, 0)$ and $r_2...