A: 正确
B: 错误
举一反三
- 中国大学MOOC: The mean is practically meaningless without information of the standard deviation.
- Given the following information: Standard deviation = 8 Coefficient of variation = 64% The mean would then be
- The difference between the sample mean and the population mean is called the: A: population deviation. B: population standard deviation. C: standard error of the mean. D: sampling error.
- When measuring the dispersion of the sample mean, the statistics to be used are ( ) . A: Coefficient of variation B: The standard deviation C: Standard deviation of the mean D: Range value
- The standard error of the mean is never larger than the standard deviation of the population.
内容
- 0
Presenting as mean ± standard deviation, the results were analyzed with SPSS 23.
- 1
Which of the following about the normal distribution is NOT true? A: Theoretically, the mean, median, and mode are the same B: About 68% of the observations fall within ±1 standard deviation from the mean C: Its parameters are the mean, μ, and standard deviation, σ D: It is a discrete probability distribution.
- 2
2.Which of the following about the normal distribution is NOT true A: Theoretically, the mean, median, and mode are the same. B: About 2/3 of the observations fall within ±1 standard deviation from the mean. C: It is a discrete probability distribution. D: Its parameters are the mean, μ, and standard deviation, σ.
- 3
Let X be a normal random variable with mean 20 and standard deviation 4. The 90th percentile of X is ____________.
- 4
Given an infinite population with a mean of 75 and a standard deviation of 12, the probability that the mean of a sample of 36 observations, taken at random from this population, exceeds 78 is: