Statistics Final 2017 - Minhui Paik
Are selecting female and an injured Alpine Ski player disjoint (mutually exclusive) events?
No, because there are outcomes in common.
Which statement is NOT TRUE about confidence intervals?
A confidence interval between 20% and 40% means that the population proportion lies between 20% and 40%.
The distribution of ages of females in the United States is strongly skewed to the left with a mean of 80.2 years, A random sample of n=20 females is taken from this population and the mean age of the sample is calculated. This is repeated i000 times. Which one of the following best describes the shape of the sampling distribution?
Approximately normal distribution with a mean of 80.2
T or F: The large p-value implies that the null hypothesis is true.
False (The large p-value implies that the null hypothesis is not true.)
T or F: Disjoint (or Mutually exclusive)events are independent.
False. (Disjoint (or Mutually exclusive)events have no outcomes in common).
If a sample size is large, then the shape of the histogram of the sample will be approximately normal, even if the population distribution is not normal.
False. (If a sample size is large, then the shape of the histogram of the sample will be close to population shape, even if the population distribution is not normal.)
T of F: Values of both a parameter and a statistic may vary from sample to sample.
False. (values of a statistic, not a parameter, may very from sample to sample.)
Which statement is NOT TRUE about the 95% confidence level?
The probability that the true value of the population parameter falls between the bounds of an already computed confidence interval is roughly 95%.
T of F Median, IQR and quartiles are least affected by outliers.
True
T or F: If a sample size is large, then the shape of the sampling distribution of the mean will be approximately normal, even if the population distribution is not normal.
True
T of F: A statistic is used to estimate a parameter.
True.
T or F: A 99% confidence interval procedure has a higher probability of capturing the population parameter than a 95% confidence interval procedure.
True.
T or F: T-distribution has a larger spread than the standard normal distribution.
True.
T or F: The standard deviation is a measure of spread, interpreted as the average distance between a data value and the data's mean.
True.
According to the central limit theorem, the sampling distribution of the mean follows a normal distribution
as the sample size (number of observations) gets "large enough".
The sampling distribution of the mean is a distribution of: (a) individual population values. (b) Individual sample values (c) statistics (d) parameters (e) none of them
statistics.