Statistics Questions
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Suppose that a population distribution is normally distributed with a mean and a standard deviation. Now, suppose that you draw an infinite number of random samples from this population with each sample consisting of 25 observations and you compute an infinite number of sample means. The standard deviation of the sample means (the standard error) is ____ as the population standard deviation
A null hypothesis should be rejected when the p-value is what?
Suppose a random sample of n = 36 observations is selected from a population with a mean µ = 256 and variance σ^2 = 144. What is the standard deviation (standard error) of the sampling distribution of the sample mean?
Suppose that your friend claims she is a 90 percent free throw shooter. While you are both on the playground, she takes 100 free throws and makes 84 of them. The test statistic associated with the null hypothesis is __________; therefore, we __________ reject the null hypothesis that she is a 90 percent free throw shooter at the 5 percent level of significance.
Suppose that you have data on the U.S. unemployment rate from 1947 to 2024. The best way to graphically illustrate this data would be to use a:
Suppose that in a criminal trial a defendant is actually innocent, but that he is found guilty of the crime. In this case,
The interquartile range (IQR) of the data {18, 12, 16, 13, 11} is what?
A frequency distribution that has positive excess kurtosis is called __________ and compared to a normal distribution with the same mean and variance, it has __________ tails.
For a sample of n ≥ 30, the sampling distribution of the mean will be approximately normally distributed:
The coefficient of variation for the data {18, 12, 16, 13, 11} is what?
A national achievement test is administered annually to 3rd graders. The distribution of scores is normal with a population mean of 100 and a population standard deviation of 15. If Jane's Z-score is 1.20, what was her score on the test?
The distribution of actual weights of 8.0 oz chocolate bars produced by a certain machine is normally distributed with a mean of 8.1 0z. and a standard deviation of 0.1 ounces. The proportion of chocolate bars weighing under 8.0 oz. is what?
The geometric mean for the data {18, 12 , 16, 13, 11} is:
Five randomly chosen people have the following years of education: {18, 12, 16, 13, 11}. The median number of years of education in this sample is:
Consider the data {18, 12, 16, 13, 11}, what is the skewness?
Which of the following would result in the narrowest confidence interval?
population or sometimes infinity
r^2% of variation in y is (explained) (accounted for) by the (regression line) (LSRL)
actual (observed) y (value) is typically s away from the predicted (y) value by the (regression line) (LSRL)
binary, independent, (number of trials not fixed,) same (fixed) probability,