问题


There is a single choice question about econometrics. Answer the question by replying A, B, C or D.
Question: Which of the following is NOT a feature of continuously compounded returns (i.e. log-returns)?
A. They can be interpreted as continuously compounded changes in the prices
B. They can be added over time to give returns for longer time periods
C. They can be added across a portfolio of assets to give portfolio returns
D. They are usually fat-tailed
Answer:

答案

模型 模型答案 正确答案
金声玉亮2.0 C. They can be added across a portfolio of assets to give portfolio returns C
deepseekr1

The correct answer is **C**.

Continuously compounded returns (log-returns) can be added over time (e.g., daily log-returns sum to weekly returns), making **B** a valid feature. However, they **cannot** be directly added across assets in a portfolio to compute portfolio returns because portfolio returns depend on the weighted sum of simple returns, not log-returns. Adding log-returns across assets ignores the nonlinear interaction between asset values.

**A** is correct as log-returns inherently represent continuously compounded changes. **D** is correct since log-returns often exhibit fat tails, similar to simple returns. Thus, **C** is the exception.

Answer: **C**
C
gpto1 C C
GPT-4o D. They are usually fat-tailed C
llama3.1-70B-Instruct

A
C
llama3.1-405B-Instruct

A
C
DeepSeek-Coder-V2 D C
Qwen2-72B-Instruct C. They can be added across a portfolio of assets to give portfolio returns

In reality, portfolio returns are calculated as a weighted average of the individual asset returns, not by simply adding them together.
C
baichuan4 D C
doubao D

Continuous compounding is a mathematical concept and does not necessarily imply fat-tailed returns. The other options are more characteristic of continuously compounded returns.
C
minimax D. They are usually fat-tailed C
kimi D. They are usually fat-tailed C
wenxinyiyan D

Explanation:
Continuously compounded returns, often referred to as log-returns, have several important properties:

A. They can be interpreted as continuously compounded changes in the prices - This is correct. Log-returns represent the continuously compounded growth rate of an asset's price over a specified period.

B. They can be added over time to give returns for longer time periods - This is also correct. Due to the additive property of logarithms, log-returns over multiple periods can be summed to obtain the total log-return for the combined period.

C. They can be added across a portfolio of assets to give portfolio returns - This is true as well. When assets are held in a portfolio, the log-returns of the individual assets can be weighted and summed to calculate the portfolio's log-return.

D. They are usually fat-tailed - This statement is NOT a general feature of log-returns. The fat-tailedness of returns refers to the higher probability of extreme events (large positive or negative returns) compared to a normal distribution. Whether returns (whether simple or log) are fat-tailed depends on the underlying data and is not inherent to the calculation method of log-returns. Log-transformation itself does not introduce or eliminate fat-tailedness.
C
zhipu C. They can be added across a portfolio of assets to give portfolio returns

Continuously compounded returns (log-returns) are not typically added across a portfolio of assets to give portfolio returns. Instead, portfolio returns are usually calculated by considering the weighted average of the individual asset returns, where the weights are based on the proportion of each asset in the portfolio. The other options describe valid features of log-returns: they can be interpreted as continuously compounded changes in prices (A), they can be added over time to give returns for longer time periods (B), and they are often characterized by fat tails (D).
C
gpto1 C C