Information Theory
This quiz covers the fundamental concepts and principles of Information Theory, including entropy, mutual information, channel capacity, and coding theorems.
Questions
What is the unit of information in Information Theory?
- Bit
- Byte
- Hertz
- Decibel
The entropy of a random variable $X$ is defined as:
- $H(X) = \sum_x p(x) \log p(x)$
- $H(X) = \sum_x p(x) \log_2 p(x)$
- $H(X) = \sum_x p(x)^2 \log p(x)$
- $H(X) = \sum_x p(x)^2 \log_2 p(x)$
The mutual information between two random variables $X$ and $Y$ is defined as:
- $I(X;Y) = H(X) + H(Y)$
- $I(X;Y) = H(X) - H(Y)$
- $I(X;Y) = H(X,Y) - H(X)$
- $I(X;Y) = H(X,Y) - H(X) - H(Y)$
The channel capacity of a communication channel is defined as:
- $C = \max_{p(x)} I(X;Y)$
- $C = \max_{p(x)} H(X)$
- $C = \max_{p(x)} H(Y)$
- $C = \max_{p(x)} H(X,Y)$
The Shannon-Hartley theorem states that the channel capacity of a band-limited additive white Gaussian noise (AWGN) channel is given by:
- $C = B \log_2 (1 + \frac{S}{N})$
- $C = B \log_2 (1 + \frac{N}{S})$
- $C = B \log_2 (1 + \frac{S}{N^2})$
- $C = B \log_2 (1 + \frac{N^2}{S})$
The source coding theorem states that the minimum number of bits required to represent a source with entropy $H$ is:
- $R = H$
- $R = H + 1$
- $R = H - 1$
- $R = 2H$
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:
- $R < C$
- $R = C$
- $R > C$
- $R \ge C$
The Huffman coding algorithm is a:
- Prefix-free code
- Variable-length code
- Fixed-length code
- Non-unique code
The Lempel-Ziv-Welch (LZW) algorithm is a:
- Lossless data compression algorithm
- Lossy data compression algorithm
- Huffman coding algorithm
- Arithmetic coding algorithm
The JPEG image compression standard uses:
- Discrete cosine transform (DCT)
- Discrete Fourier transform (DFT)
- Walsh-Hadamard transform (WHT)
- Haar wavelet transform
The MP3 audio compression standard uses:
- Perceptual audio coding (PAC)
- Linear predictive coding (LPC)
- Adaptive differential pulse-code modulation (ADPCM)
- Transform coding
The H.264 video compression standard uses:
- Block-based motion compensation
- Discrete cosine transform (DCT)
- Quantization
- Entropy coding
The information content of a message is measured in:
- Bits
- Bytes
- Hertz
- Decibels
The rate of a source code is defined as:
- The number of bits required to represent a single source symbol
- The number of bits required to represent a block of source symbols
- The average number of bits required to represent a source symbol
- The maximum number of bits required to represent a source symbol
The efficiency of a source code is defined as:
- The ratio of the entropy of the source to the rate of the code
- The ratio of the rate of the code to the entropy of the source
- The ratio of the average length of a codeword to the entropy of the source
- The ratio of the entropy of the source to the average length of a codeword