When Reading a Research Journal,a 46-Year-Old Professor Finds That She

question 70

Multiple Choice

When reading a research journal,a 46-year-old professor finds that she must hold it farther away to read the fine print.She is experiencing which normal age-related change in vision?

• A) presbycusis
• B) retinopathy
• C) presbyopia
• D) dysthermia

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Definitions:

Tchebysheff's Theorem

A statistical theorem stating that for any distribution, the proportion of outcomes within k standard deviations from the mean is at least \(1-\frac{1}{k^2}\) for k > 1.

Empirical Rule

A statistical norm indicating that in a normal distribution, the vast majority of data points lie within a range of three standard deviations from the mean.

Tchebysheff's Theorem

A theorem that provides a minimum bound on the proportion of values that lie within a certain number of standard deviations from the mean for any distribution.

Empirical Rule

The rule in statistics where for any normal distribution, practically all of the data is expected to be within three standard deviations from the mean value.