Question

Obesity: The National Center for Health Statistics conducted the National Health Interview Survey (NHIS) for 27,787 U.S. civilian noninstitutionalized adults in January – September 2014. According to an early release report, an estimated 29.9% of U.S. adults aged 20 and over were obese. Obesity is defined as a body mass index (BMI) of 30 kg/m 2 or more. True or false? The 29.9% is a parameter representing a population of 27,787 adults. (Source: Ward BW, Clarke TC, Freeman G, Schiller JS. (2015) Early release of selected estimates based on data from the January–September 2014 National Health Interview Survey. National Center for Health Statistics.)

Answer 1

The correct answer is 'False'

Explanation:

In statistical analysis, the parameter represents a characteristic (usually numerical) that describes the entire population.

The parameter gives a clear picture of that characteristic (usually numerically) for the entire population, after sampling the entire population.

The sample equivalent of a parameter is called a statistic. A statistic describes that same characteristic (usually numerically), for a sample taken from the population.

The number of people that participated in this survey (27,787), although large, isn't the entire population of adults aged 20 and above in the U.S.

So, the 29.9% proportion of the sample surveyed that were found to be obese is at best a good estimation of the population proportion (due to the very large sample size).

It is however not correct, to say that the 29.9% is a parameter representing a population of 27,787 adults.

So, the 29.9% is more appropriately a statistic for the 27,787 adults sample.

Hope this Helps!!!