Exam 6: Statistics

A poll on a cigarette tax increase includes the following: "Last year, cigarette taxes funded an extra one hundred child healthcare projects in the state. Do you favor a cigarette tax increase?" Does this question show any bias?

Suppose we toss 150 fair coins and record the percentage of heads. According to the central limit theorem, the percentages of heads resulting from such experiments are approximately normally distributed. Find the standard deviation of this normal distribution.

Suppose that for a certain illness, the probability is 40% that a given patient will improve without treatment. Then the probability that at least n out of 20 patients will improve without treatment is given in the following table: We gave an experimental drug to 20 patients who have the illness and 11 patients showed improvement. What is the p-value?

The average yearly high temperature in a certain city is recorded. It is found that the mean temperature is 70.2°F with a standard deviation of 8.2°F. Assuming that the data are normally distributed, in what range should 68% of the data lie?

A correlation coefficient whose magnitude is between 0.5 and 0.8 indicates _______________ linear correlation.

A _______________ p-value is usually interpreted as evidence that the event in question is unlikely to be due to chance alone.

The _______________ quartile is the median of the upper half of the numbers in a list.

The median of a list of numbers arranged from smallest to largest is the _______________ number.

Assume we know that 20% of Americans suffer from a certain type of allergy. Suppose we take a random sample of 8000 Americans and record the percentage who suffer from this allergy. What guarantees that percentages from such a survey will be normally distributed?

A(n) _______________ is a data point that is significantly different from most of the data.

Michael's five test scores in his physics class were 75, 67, 88, 91, and 84. What was his mean test score?

Consider the pair of variables: The number of touchdowns thrown by Tom Brady and the number of bills in your wallet. These variables are:

A polling organization conducts a poll by making a random survey of 1250 people. Estimate the margin of error at a confidence interval of 95%.

It is known that in the absence of treatment, 68% of the patients with a certain illness will improve. The central limit theorem tells us that the percentages of patients in groups of 500 that improve in the absence of treatment are approximately normally distributed. Find the standard deviation of the normal distribution given by the central limit theorem.

An auto dealer's sales numbers are shown in the table below. Find the mode price for the cars sold in August.

A correlation coefficient near 0 indicates little if any _______________ correlation.

Ridge counts on fingerprints are approximately normally distributed, with a mean of about 140 and a standard deviation of 50. It then follows that 68% of the population will have:

Determine which figure shows the strongest linear relationship.

Consider the pair of variables: Time you spend running on a track and calories you will burn. These variables are:

For data points above the mean, the z-score is _______________.