Question: The assumption for normality usually holds in any distribution so long as precise calculations of z statistics are made.
Answer Choices: True False
Answer: False
Question: Which of the following statistics is not necessary to know prior to performing a sample size calculation?
Answer Choices: The population standard deviation The set power and alpha level of your test The sensitivity of the test The detectable difference worth measuring
Answer: The sensitivity of the test
Question: What happens to the standard error of an estimate when the sample size in a SRS decreases?
Answer Choices: The standard error stays roughly the same The precision of the estimate increases The precision of the estimate decreases The standard error gets smaller
Answer: The precision of the estimate decreases
Question: Which of the following best describes the meaning behind the area under the probability-density function’s smooth curve?
Answer Choices: The range of possible outcomes; The standard deviation of the distribution; The probability associated with the specified range of outcomes; The shape and spread of the distribution
Answer: The probability associated with the specified range of outcomes
Question: While observing the smooth curve overlaying the probability-density function, ______ are used to identify points that are one standard deviation above and below the mean.
Answer Choices: N/A
Answer: Vertical lines (reference lines)
Question: Changing the μ of a distribution does what to the probability-density function?
Answer Choices: Shifts the distribution on the horizontal axis; Shifts the distribution on the vertical axis; Determines the spread of the distribution; None of the above
Answer: Shifts the distribution on the horizontal axis
Question: Researchers pre-establish the rate of false rejection of the null hypothesis prior to conducting any testing for significance.
Answer Choices: True False
Answer: True
Question: Which of the following statistics is not necessary to know prior to performing a power calculation for a one-sample z test?
Answer Choices: The detectable difference worth measuring The false positive rate of the test The population standard deviation The sample size The alpha level for confidence
Answer: The sample size
Question: Which of the following p-values can be considered statistically highly significant?
Answer Choices: 0.001 0.01 0.1 0.07 0.001 and 0.01
Answer: 0.001 and 0.01
Question: Which of the following are least likely to be the primary means of investigating normality in a distribution X?
Answer Choices: Graphically display a histogram and use the eyeball test; Observe a computerized Q-Q plot; Calculate observed and expected z-scores; Start with a normal approximation, as most continuous variables are normal
Answer: Start with a normal approximation, as most continuous variables are normal
Question: Variability in a distribution that would be otherwise non-normal may tend towards normality with random sampling.
Answer Choices: True; False
Answer: True
Question: Which of the following requisites for a Z test are unnecessary in formal testing of significance?
Answer Choices: A known σ prior to initiation of testing A population large enough to approximate normality via the Central Limit Theorem A SRS or reasonable approximation thereof A set level for power of a test
Answer: A set level for power of a test