Instruction 15-6
Four Surgical Procedures Currently Are Used to Install

question 29

Short Answer

Instruction 15-6
Four surgical procedures currently are used to install pacemakers. If the patient does not need to return for follow-up surgery, the operation is called a 'clear' operation. A heart centre wants to compare the proportion of clear operations for the four procedures, and collects the following numbers of patients from their own records:
| Procedure |
$$\begin{array} { | l | c | c | c | c | c | } \hline & \text { A } & \text { B } & \text { C } & \text { D } & \text { Total } \\\hline \text { Clear } & 27 & 41 & 21 & 7 & 96 \\\hline \text { Return } & 11 & 15 & 9 & 11 & 46 \\\hline \text { Total } & 38 & 56 & 30 & 18 & 142 \\\hline\end{array}$$ They will use this information to test for a difference among the proportion of clear operations using a chi-square test with a 0.05 level of significance.
-Referring to Instruction 15-6,what is the value of the critical range for the Marascuilo procedure to test for the difference in proportions between procedure A and procedure D using a 0.05 level of significance?

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Definitions:

Mid-Ocean Ridges

Underwater mountain systems formed by plate tectonics, consisting of various mountains linked in chains.

Contact Metamorphism

Contact metamorphism occurs when rocks are heated to high temperatures and sometimes subjected to increased pressures due to the close proximity of magma or lava, without melting the rock completely.

Normal Faults

A type of fault where the hanging wall moves downward relative to the footwall, typically a result of extensional forces pulling the crust apart.

Hot Seawater

Seawater that has been heated, often by geothermal activity under the ocean floor, impacting marine life and ecosystems.