Stats M1 Test

A researcher wants to study sleep deprivation in college students. She randomly selects 50 students from a local college and asks them how many hours of sleep they get on a typical night. Her results are shown in the table below. What proportion of students get between 4 and 6.99 hours of sleep a night?

0.52

Which of the following data lists is represented by this frequency table:

1, 1, 1, 2, 3, 3, 4, 4, 4, 4, 4, 4, 5, 5, 6, 6, 6, 6

The relative frequency histogram below shows the level of cholesterol (in mg per dl) of 100 people. How many people have a level of cholesterol between 205 and 210 mg per dl?

20

A zookeeper takes a sample of 50 penguins and finds their average weight to be 51 lb with a standard deviation of 4 lb. How would you find a z - score corresponding to a penguin that weighs 52 lb in Excel?

= (52 - 51) /4

How would you type the equation "eight divided by six" in Excel?

= 8/6

The square root of the ____(a)_____ is called the ____(b)_____ .

A. Variance B. Standard Deviation

The mean score on a standardized math exam is 72.6; the standard deviation is 10.5. Paul is told that the z-score of his exam score is 1.2. Is Paul's score above average or below average? above average

Above Average

Mean, median, and mode are all measures of the [ Select ] ["spread", "randomness", "center", "reliability"] of a data set, while variance and standard deviation measure the [ Select ] ["spread", "randomness", "center", "reliability"] of a data set.

Center, spread

Median and average are the same thing.

False

The following data and output from Excel represents the Test #1 Score for an Intro to Statistics course at a college: Use this information to answer the following question: Based on the output from Excel, it shows the Median is 85. Explain what it means in the context of the data.

Half of students scored below 85 and another half scored above 85

Which student(s) has a test score farthest from the mean?

Hartz

Is temperature in ^oC nominal, ordinal, interval, or ratio?

Interval Scale

A cop measures the speeds of drivers on a highway. The average speed is 70 mph. However, a truck is struggling to go uphill and is driving 50 mph. What can the cop say about their z - score?

It is negative

Which of the following would NOT be an appropriate measure of central tendency when looking at incomes of a middle class neighborhood when one neighbor just sold their startup idea to Facebook for $1,000,000?

Mean

Which of the following statistics is least impacted by outliers?

Median

Is religious preference (i.e. Christian, Buddhist, Muslim, etc.) nominal, ordinal, interval, or ratio?

Nominal

Identify the following as either qualitative, quantitative discrete, or quantitative continuous: House numbers on a particular street

Qualitative

Identify the following as either qualitative, quantitative discrete, or quantitative continuous: Number of students responding to a survey about their names

Quantitative Discrete

The difference between the maximum and minimum value is called the __________.

Range

Determine the level of measurement of the variable: Weight of rice bought by a customer

Ratio

Managers at a hospital are interested in the length of stay (in days) of open-heart patients who underwent surgery within the last year. Thirty five open-heart surgery patients admitted to the hospital within the last year are selected. Identify the population, sample, parameter, statistic, and variable in this problem.

Sample - 35 who underwent surgery Parameter - average length of stay of all patients Variable - length of stay Population - All patients Statistic - average length of stay of the 35

A geographer randomly selects twenty points in a county to study the elevation. One point is on a large hill while the other points are near water level. What is the shape of the distribution?

Skewed Right

Every fifth adult entering an airport is checked for extra security screening. What sampling technique was used?

Systematic

A psychologist wants to study whether there is a correlation between sleep deprivation and the diagnosis of ADD in students. She randomly selects 20 students who are diagnosed with ADD and times how long they are asleep. She found the students slept, on average, six hours a night. What is the sample?

The 20 students studied

Use this information to answer the following question: Which of the following statement best describe the test.

The test is relatively easy for most students

If the z-score corresponding to the weight of a newborn baby is -3, which of the following statements best describes the newborn's weight?

This is a very light baby in comparison to other newborn babies.

The standard deviation of a numerical data set measures the ____________ of the data.

Variability

A parameter is

a numerical description of a population characteristic

The Department of Education wishes to estimate the proportion of all college students who have a job off-campus. It surveyed 1600 randomly selected students; 451 had such jobs. The population of interest to the Department of Education is:

all college students who have a job off campus