Information Theory

This quiz covers the fundamental concepts and principles of Information Theory, including entropy, mutual information, channel capacity, and coding theorems.

15 Questions Published

Questions

Question 1 Multiple Choice (Single Answer)

What is the unit of information in Information Theory?

  1. Bit
  2. Byte
  3. Hertz
  4. Decibel
Question 2 Multiple Choice (Single Answer)

The entropy of a random variable $X$ is defined as:

  1. $H(X) = \sum_x p(x) \log p(x)$
  2. $H(X) = \sum_x p(x) \log_2 p(x)$
  3. $H(X) = \sum_x p(x)^2 \log p(x)$
  4. $H(X) = \sum_x p(x)^2 \log_2 p(x)$
Question 3 Multiple Choice (Single Answer)

The mutual information between two random variables $X$ and $Y$ is defined as:

  1. $I(X;Y) = H(X) + H(Y)$
  2. $I(X;Y) = H(X) - H(Y)$
  3. $I(X;Y) = H(X,Y) - H(X)$
  4. $I(X;Y) = H(X,Y) - H(X) - H(Y)$
Question 4 Multiple Choice (Single Answer)

The channel capacity of a communication channel is defined as:

  1. $C = \max_{p(x)} I(X;Y)$
  2. $C = \max_{p(x)} H(X)$
  3. $C = \max_{p(x)} H(Y)$
  4. $C = \max_{p(x)} H(X,Y)$
Question 5 Multiple Choice (Single Answer)

The Shannon-Hartley theorem states that the channel capacity of a band-limited additive white Gaussian noise (AWGN) channel is given by:

  1. $C = B \log_2 (1 + \frac{S}{N})$
  2. $C = B \log_2 (1 + \frac{N}{S})$
  3. $C = B \log_2 (1 + \frac{S}{N^2})$
  4. $C = B \log_2 (1 + \frac{N^2}{S})$
Question 6 Multiple Choice (Single Answer)

The source coding theorem states that the minimum number of bits required to represent a source with entropy $H$ is:

  1. $R = H$
  2. $R = H + 1$
  3. $R = H - 1$
  4. $R = 2H$
Question 7 Multiple Choice (Single Answer)

The channel coding theorem states that it is possible to achieve reliable communication over a noisy channel with a capacity of $C$ by using a code with a rate:

  1. $R < C$
  2. $R = C$
  3. $R > C$
  4. $R \ge C$
Question 8 Multiple Choice (Single Answer)

The Huffman coding algorithm is a:

  1. Prefix-free code
  2. Variable-length code
  3. Fixed-length code
  4. Non-unique code
Question 9 Multiple Choice (Single Answer)

The Lempel-Ziv-Welch (LZW) algorithm is a:

  1. Lossless data compression algorithm
  2. Lossy data compression algorithm
  3. Huffman coding algorithm
  4. Arithmetic coding algorithm
Question 10 Multiple Choice (Single Answer)

The JPEG image compression standard uses:

  1. Discrete cosine transform (DCT)
  2. Discrete Fourier transform (DFT)
  3. Walsh-Hadamard transform (WHT)
  4. Haar wavelet transform
Question 11 Multiple Choice (Single Answer)

The MP3 audio compression standard uses:

  1. Perceptual audio coding (PAC)
  2. Linear predictive coding (LPC)
  3. Adaptive differential pulse-code modulation (ADPCM)
  4. Transform coding
Question 12 Multiple Choice (Single Answer)

The H.264 video compression standard uses:

  1. Block-based motion compensation
  2. Discrete cosine transform (DCT)
  3. Quantization
  4. Entropy coding
Question 13 Multiple Choice (Single Answer)

The information content of a message is measured in:

  1. Bits
  2. Bytes
  3. Hertz
  4. Decibels
Question 14 Multiple Choice (Single Answer)

The rate of a source code is defined as:

  1. The number of bits required to represent a single source symbol
  2. The number of bits required to represent a block of source symbols
  3. The average number of bits required to represent a source symbol
  4. The maximum number of bits required to represent a source symbol
Question 15 Multiple Choice (Single Answer)

The efficiency of a source code is defined as:

  1. The ratio of the entropy of the source to the rate of the code
  2. The ratio of the rate of the code to the entropy of the source
  3. The ratio of the average length of a codeword to the entropy of the source
  4. The ratio of the entropy of the source to the average length of a codeword