This review is optional but will give excellent practice for the test.
This review is optional but will give excellent practice for the test.
A study of voting chose 663 registered voters at random shortly after an election. Of these, 72% said they had voted in the election. Election records show that only 56% of registered voters voted in the election.
Match up the following statements about these percentages?
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
All voters | arrow_right_alt | Parameter |
663 regsitered voters | arrow_right_alt | Statistic |
56% | arrow_right_alt | Sample |
72% | arrow_right_alt | Population |
Vermont is particularly beautiful in early October when the leaves begin to change color. At that time of year, a large proportion of cars on Interstate 91 near Brattleboro have out-of-state license plates.
Suppose a Vermont state trooper randomly selects 50 cars driving past Exit 2 on I-91, records the state identified on the license plate, and calculates the proportion of cars with out-of-state plates.
What is the Vermont state trouper recording?
Which of the following describes the sampling distribution of the sample proportion in this context?
A polling organization wants to estimate the proportion of voters who favor a new law banning smoking in public buildings.
The organization decides to increase the size of its random sample of voters from about 1500 people to about 4000 people right before an election.
The effect of this is to
The central limit theorem is important in statistics because it allows us to use the normal distribution to find probabilities involving the sample mean if the
Using the information in the previous problem, what is the Normal Model?
Use the notation N(
Scores on the mathematics part of the SAT exam in a recent year followed a normal distribution with mean 515 and standard deviation 114.
You choose an SRS of 100 students and calculate mean SAT Math score.
Match up the following for this situation.
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
11.4 | arrow_right_alt | sample size (n) |
100 | arrow_right_alt | |
515 | arrow_right_alt | |
114 | arrow_right_alt |
Use the information in the previous question.
What is the probability of getting a sample of 100 registered voters with more than 65% democrats?
Keep all decimals.
Using the information above, suppose an actual sample of 100 of the registered voters actually resulted in 65% democrats. Would you have convincing evidence that the estimated 52% democrat voters was incorrect? Explain.
Use the information from the previous question:
What is the shape of the population and the sampling distribution of x-bar ? Justify.
Match the correct notation with the definition.
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
| arrow_right_alt | Population Mean | |
| arrow_right_alt | Population Proportion | |
X-bar | arrow_right_alt | Mean of the Sampling Distribution of Means |
| arrow_right_alt | Mean of the Sampling Distribution of Proportions | |
| arrow_right_alt | Sample Mean | |
| arrow_right_alt | Sample proportion | |
p-hat | arrow_right_alt | Standard Deviation of the Sampling Distribution of means |
| arrow_right_alt | Standard Deviation of the Sampling Distribution of proportions |
The student newspaper at a large university asks an SRS of 250 undergraduates, “Do you favor eliminating the carnival from the end-of-term celebration?”
In the sample, 150 of the 250 undergraduates are in favor.
Suppose that 55% of all undergraduates favor eliminating the carnival. If you took a very large number of SRSs of size n = 250 from this population, the sampling distribution of the sample proportion p-hat would have which of the following characteristics?