Blog

Standards and calibrators differ from control materials because:

Provide an appropriate response.Given the equation of a regression line is = -4.5x- 2.4, what is the best predicted value for y given x=2.3?

Provide an appropriate response.The commuting times (in minutes) of an employee for ten consecutive days are listed below. Find the median commute.71, 67, 67, 72, 76, 72, 73, 68, 72, 72

Determine whether the underlined value is a parameter or a statistic.25.2% of the mayors of cities in a certain state are from minority groups.

Provide an appropriate response.Given the following five-number summary, find the interquartile range (IQR).2.9, 5.7, 10.0, 13.2, 21.1.

Provide an appropriate response.The book cost (in dollars) for one semester’s books are given below for a sample of five college students. Calculate the sample variance of the book costs. 205, 140, 395, 500, 255

Find the sample standard deviation.65, 39, 73, 87, 43, 37, 29, 81, 56

Provide an appropriate response.Parking at a large university has become a very big problem. University administrators are interested in determining the average parking time (e.g. the time it takes a student to find a parking spot) of its students. An administrator inconspicuously followed 210 students and carefully recorded their parking times. Identify the sample of interest to the university administration.

Determine whether the underlined value is a parameter or a statistic.Telephone interviews of 318 employees of a large electronics company found that 45% were dissatisfied with their working conditions.

Provide an appropriate response.A study was designed to investigate the effects of two variables – (1) a student’s level of mathematical anxiety and (2) teaching method – on a student’s achievement in a mathematics course. Students who had a low level of mathematical anxiety were taught using the traditional expository method. These students obtained a mean score of 260 with a standard deviation of 40 on a standardized test. Assuming a bell-shaped distribution, where would approximately 95% of the students score?