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Chapter 1: Problem 15

The article "Bicyclists and Other Cyclists" (Annals of Emergency Medicine [2010]: 426) reported that in 2008 , 716 bicyclists were killed on public roadways in the United States and that the average age of the cyclists killed was 41 years. These figures were based on an analysis of the records of all traffic-related deaths of bicyclists on U.S. public roadways (this information is kept by the National Highway Traffic Safety Administration). a. Does the group of 716 bicycle fatalities represent a census or a sample of the bicycle fatalities in \(2008 ?\) b. If the population of interest is bicycle traffic fatalities in 2008 , is the given average age of 41 years a statistic or a population characteristic?

Short Answer

Expert verified
a) The group of 716 bicycle fatalities represent a census. b) The average age of 41 years is a population characteristic.

Step by step solution

01

Problem Identification

In this task, the data presented reflect all the deaths of cyclists that took place on public roads in the US within the year 2008. a) You are tasked to decide whether this data set is a census or a sample. b) Then, if the population of interest is the bicycle traffic fatalities in 2008, determine whether the average age of 41 years is a statistic or a population characteristic.
02

Census or Sample

The data set shared in the problem includes every bicycle fatality that occurred on U.S. public roadways in 2008. Therefore, it represents the entire population of interest for this particular year. Thereby, one can classify this as a census rather than a sample since all instances of the event are considered and there is no selection or sub-sampling involved.
03

Statistic or Population Characteristic

The average age of the cyclists killed, given as 41 years, is calculated based on the entire population of cyclists' deaths for that year. This figure is therefore not a statistic that results from a sample of the data, but a characteristic of the entire population for that time frame. In other words, this is a population characteristic.

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