AP Statistics Unit 6 Review

Recent revenue shortfalls in a Midwestern state led to a reduction in the state budget for higher education. To offset the reduction, the largest state university proposed a 25% tuition increase. It was determined that such an increase was needed simply to compensate for the lost support from the state. Separate random samples of 50 freshmen, 50 sophomores, 50 juniors, and 50 seniors from the university were asked whether or not they were strongly opposed to the increase, given that it was the minimum increase necessary to maintain the university’s budget at the current levels. The results are given in the table. The conditions for carrying out the chi-square test is: I. Separate random samples from the populations of interest II. Expected counts large enough III. The samples themselves and the individual observations in each sample are independent. Which of the conditions is (are) satisfied in this case?

• I only

• II only

• I and II only

• II and III only

• I, II and III

A random sample of traffic tickets given to motorists in a large city is examined. The tickets are classified according to the race of the driver. The results are summarized in the table. We wish to test H0: The racial distribution of traffic tickets in the city is the same as the racial distribution of the city’s population. The category that contributes the largest component to the X2 statistic is

• White

• Black

• Hispanic

• Other

• The answer cannot be determined since this is only a sample

All current-carrying wires produce electromagnetic (EM) radiation, including the electrical wiring running into, through, and out of our homes. High-frequency EM radiation is thought to be a cause of cancer. The lower frequencies associated with household current are generally assumed to be harmless. To investigate this, researchers visited the addresses of a random sample of children who had died of some form of cancer (leukemia, lymphoma, or some other type) and classified the wiring configuration outside the dwelling as either a high-current configuration (HCC) or a low-current configuration (LCC). Data is given in the table.Computer software was used to analyze the data.X2 = 0.082 + 0.170 + 0.023 + 0.048 + 0.099 + 0.013 = 0.435The appropriate degrees of freedom for the statistic is

• 1

• 2

• 3

• 4

• 5

All current-carrying wires produce electromagnetic (EM) radiation, including the electrical wiring running into, through, and out of our homes. High-frequency EM radiation is thought to be a cause of cancer. The lower frequencies associated with household current are generally assumed to be harmless. To investigate this, researchers visited the addresses of a random sample of children who had died of some form of cancer (leukemia, lymphoma, or some other type) and classified the wiring configuration outside the dwelling as either a high-current configuration (HCC) or a low-current configuration (LCC). Data is given in the table. Computer software was used to analyze the data. X² = 0.082 + 0.170 + 0.023 + 0.048 + 0.099 + 0.013 = 0.435 Which of the following may we conclude, based on the test results?

• There is strong evidence of an association between wiring configuration and the chance that a child will develop some form of cancer.
  

• HCC either causes cancer directly or is a major contributing factor to the development of cancer in children.
  

• Leukemia is the most common type of cancer among children. 
  

• There is not convincing evidence of an association between wiring configuration and the type of cancer that caused the deaths of children in the study.
  

• There is a weak evidence that HCC causes cancer in children. 
  

All current-carrying wires produce electromagnetic (EM) radiation, including the electrical wiring running into, through, and out of our homes. High-frequency EM radiation is thought to be a cause of cancer. The lower frequencies associated with household current are generally assumed to be harmless. To investigate this, researchers visited the addresses of a random sample of children who had died of some form of cancer (leukemia, lymphoma, or some other type) and classified the wiring configuration outside the dwelling as either a high-current configuration (HCC) or a low-current configuration (LCC). Data is given in the table. Computer software was used to analyze the data. X² = 0.082 + 0.170 + 0.023 + 0.048 + 0.099 + 0.013 = 0.435. A Type I error would occur if we conclude that

• HCC wiring caused cancer when it actually didn’t. 
  

• HCC wiring didn’t cause cancer when it actually did. 
  

• There is no association between the type of wiring and the form of cancer when there actually is an association.
  

• There is an association between the type of wiring and the form of cancer when there actually is no association.
  

• The type of wiring and the form of cancer have a positive correlation when they actually don’t. 
  

The manager of a high school cafeteria is planning to offer several new types of food for student lunches in the following school year. She wants to know if each type of food will be equally popular so she can start ordering supplies and making other plans. To find out, she selects a random sample of 100 students and asks them, "Which type of food do you prefer: Asian food, Mexican food, pizza, or hamburgers?" The table shows the data. The chi-square statistic is

If we are looking at a boxplot and notice that the distribution is skewed right, what measure of center should we use?

• Mean

• Mode

• Median

• IQR

Given the five number summary below, find the IQR:

5,8,10,14,26

• 21

• 6

• 10

• 9

If the mean and median of a distribution are equal, what does this tell us about the shape?

• Symmetric

• Unimodal

• Skewed Right

• Skewed Left

We are given a distribution that is symmetric, what measure of spread should we use?

• Mean

• IQR

• Mode

• Standard Deviation