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Chapter 6: Binomial & Geometric Distribution
Chapter 9: Estimating a Population Proportion
Chapter 12: Estimating a Population Mean (Sigma is known)
Chapter 12: Estimating a Population Mean (Sigma is unknown)
Choosing a Sample Size/Miscellaneous
100
True/False Binomial distribution is fixed number of trials while geometric distribution is number of trials until the first success.
What is true?
100
State what makes a statistic a good estimator of a population characteristic.
What is unbiased and a small standard error?
100
Give two examples of a parameter.
What is μ and sigma?
100
How do you know when to use the t critical value?
What is when sigma is not known?
100
What do we use for p when computing margin of error prior to collecting sample statistics? (Hint: for a population proportion formula)
What is 0.5?
200
True/False The properties for both binomial distribution and geometric distribution states that the trials are independent, each trial can result in both of possible outcomes, and the probability is the same for each trial.
What is false?
200
Calculate standard error when p=.56 and and n=32. (3 decimal places)
What is .088?
200
If sample size increases, sample variability ____.
What is decreases?
200
How does t-curve relate to z-curve distribution?
What is the t-distribution becomes more similar to the z-curve as degrees of freedoms increases?
200
When sigma is known, how do we choose a sample size based on the sample?
What is use the formula (z-critical value)*(sigma/square root of n)?
300
If its possible values are isolated points along the number line it is said to be a ______. (Hint: P(x) can be greater than 0 but less than 1.)
What is discrete random variable?
300
State the conditions for a p(hat) sampling distribution.
What is (n*p(hat)) greater than or equal to 10? What is n(1-p(hat)) greater than or equal to 10?
300
State the conditions and rules of estimating a population mean when sigma is known.
What is The sampling distribution of x bar is centered at μ, The standard deviation of x bar is (sigma/square root of n), As long as n is large (n ≥ 30), the sampling distribution of x bar is approximately normal.
300
True/False As the number of degrees of freedom increases, the spread of the t-distribution decreases.
What is true?
300
Using a 90% confidence level, choose a sample size (n) prior to collecting the sample statistics when sigma is unknown. Data: 50-125 (range) M=.60
What is 2,643?
400
How do you find a probability that appears at P(x< or = 3)?
What is add p(1), p(2), p(3)?
400
Find the z critical value for 92% confidence level.
What is z critical value of 1.75?
400
A study reported a mean annual cosmic radiation dose of 219 mrem for a sample of flight personnel of Xinjiang Airlines. Suppose this mean is based on a random sample of 100 flight crew members and that sigma=35 mrems. Construct a 95% confidence interval for population mean.
What is (212.14, 225.86)?
400
FREE SPACE: What chapters are on the exam #2?
What is 6.7, 7, 8, 9, 12.1, 12.2?
400
Find a t critical value for a 93% confidence interval and when n=12.
What is a t critical value of 2.0?
500
We know 60% of all computers sold by the large computer retailer are laptops and 40% are desktop models. The type of computer purchased by each of the next 12 customers will be recorded. State whether it is binomial or geometric distribution. Then answer: what is the probability that exactly 4 of the next 12 computers are laptops?
What is binomial distribution and what is .042?
500
Of 1100 drivers surveyed, 990 admitted to careless or aggressive driving during the previous 6 months. Assuming that it is reasonable to regard this sample as a representative of the population of drivers, compute a 90% confidence interval to estimate p, the proportion of all drivers who have engaged in careless or aggressive driving in the last 6 months.
What is (0.885,0.915)? AND What is assuming that the sample was representative of the population, you can be 90% confident that the actual proportion of drivers who engaged in careless or aggressive driving in the past 6 months is somewhere between 0.885 and 0.915?
500
In a study of academic procrastinators, the authors of the paper reported that for a sample of 435 undergraduate students at a mid-size public university, the mean time spent studying for a final statistics exam is 7.85 hours and the standard deviation of study time was 3.12. Construct a 95% confidence interval estimate for the population mean.
What is (7.56, 8.14)? What is you can be 95 % confident that the actual value of population mean for time spent studying for a final statistics exam is between 7.56 and 8.14.
500
An article summarized a survey of 1,000 randomly selected Canadian residents. Each individual was asked how much he/she anticipated spending on Halloween. The resulting sample mean and standard deviation were $46.65 and $83.70. Construct a 99% confidence interval for the mean anticipated Halloween expense for Canadian residents.
What is (39.821, 53.479)?
500
Analyze this analogy: Categorical: Proportions as Numerical:______
What is Means?