Consider a Study Testing Whether Birds Were Equally Likely to Rest

question 24

Multiple Choice

Consider a study testing whether birds were equally likely to rest on each streetlight. Researchers surveyed 30 randomly chosen streetlights in a city known to have many birds and counted the number of birds resting on each streetlight. Data on the number of birds seen on the lights are shown. (Note: No lights had more than three birds.) Assuming a Poisson process, what is the expected number of streetlights without any birds?
?
$\begin{array}{|cc|}\hline \begin{array}{l}\text { Number } \\\underline {\text { birds }}\end{array} & \begin{array}{l}\text { Number } \\\underline {\text { of lights }}\end{array} \\0 & 3 \\1 & 12 \\2 & 9 \\\geq 3 & 6 \\\hline\end{array}$

• A) 3.06
• B) 4.06
• C) 5.06
• D) 6.06

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Definitions:

Control Limits

Statistical boundaries within a control chart that distinguish between random variation from the process and variation due to changes in the process.

Average Range

A statistical measure used to establish the central tendency or typical value of a set of numbers, calculated as the difference between the highest and the lowest values in a dataset.

X-bar

Another term for X-bar charts, it represents the mean value in a set of data as part of statistical quality control processes.

Sampling Distribution

The probability distribution of a given statistic based on a random sample, used to make inferences about the population.