Exam 2: Descriptive Statistics

A company collected the ages from a random sample of its middle managers with the resulting frequency distribution shown below: Class Interval Frequency 20 to <25 8 25 to <30 6 30 to <35 5 35 to <40 12 40 to <45 15 45 to <50 7 -What is the relative frequency for the largest interval?

According to a survey of the top 10 employers in a major city, a worker spends an average of 413 minutes a day on the job. Suppose the standard deviation is 26.8 minutes and the time spent is approximately a normal distribution. -According to Chebyshev's Theorem,at least what percentage of measurements in a data set will be within 3.2 standard deviations of the mean?

The values given below are snow depths measured as part of a study of satellite observations and water resources (mean = 16). 19, 18, 12, 25, 22, 8, 8, 16 -What is the standard deviation?

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m.). They selected 13 patrons and had them get in line between 2 and 3 p.m. Each was given a stop watch to record the time they spent in line. The times recorded were as follows (in minutes): 118, 124, 108, 116, 99, 120, 148, 118, 119, 121, 45, 130, 118 -What is the median?

A quantity that measures the variation of a population or a sample relative to its mean is called the ____.

Which of the following sample statistics is a measure of variation that is based only on the minimum and maximum values in a sample?

Range is a better measure of variation than standard deviation.

Twenty students were randomly selected from a business statistics course and were asked to report the number of times that they had eaten a meal at the university's cafeteria within the past month. Below are the values reported: 7, 8, 10, 11, 8, 6, 10, 9, 9, 8, 13, 12, 8, 11, 11, 14, 8, 7, 10, 12 -What is the 10^th percentile?

What would be the class length that would be used in creating a frequency histogram?

All of the following are measures of central tendency except the _____.

A graphical portrayal of a data set that divides the data into classes and gives the frequency of each class is a(n)_____.

In a rating of the satisfaction with their instructor, 13 students gave the following scores from a scale of 1 to 5; 3, 2, 1, 1, 5, 5, 4, 3, 3, 2, 4, 3, 3 -What is the IQR?

In a rating of the satisfaction with their instructor, 13 students gave the following scores from a scale of 1 to 5 (mean = 3): 3, 2, 1, 1, 5, 5, 4, 3, 3, 2, 4, 3, 3 -What is the range?

In a statistic class, 10 scores were randomly selected with the following results were obtained: 74, 73, 77, 77, 71, 68, 65, 77, 67, 66 -What is the mean?

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m.). They selected 13 patrons and had them get in line between 2 and 3 p.m. Each was given a stop watch to record the time they spent in line. The times recorded were as follows (in minutes) 118, 124, 108, 116, 99, 120, 148, 118, 119, 121, 45, 130, 118 -What are the inner fences?

In a statistic class, 10 scores were randomly selected with the following results were obtained (mean = 71.5): 74, 73, 77, 77, 71, 68, 65, 77, 67, 66 -What is the standard deviation?

In a hearing test, subjects estimate the loudness (in decibels) of sound, and the results are: 68, 67, 70, 71, 68, 75, 68, 62, 80, 73, 68 -What is the mode?

The reaction time in seconds to a stop light of a group of adult men were found to be 0.74, 0.71, 0.41, 0.82, 0.74, 0.85, 0.99, 0.71, 0.57, 0.85, 0.57, 0.55 -What is the mode?

_____________ and ____________ are used to describe qualitative (categorical)data.

Compute the population variance of the data: 16,18,23,21,17,16,24,23,9,17,11,16,22,10,15,14.