TABLE 12-9
Four Surgical Procedures Currently Are Used to Install

question 110

Short Answer

TABLE 12-9
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 center wants to compare the proportion of clear operations for the 4 procedures, and collects the following numbers of patients from their own records:
$$\begin{array}{l}\text {\quad\quad\quad\quad\quad\quad\quad Procedure }\\\begin{array} { l | r r r r | r } & \text { A } & \text { B } & \text { C } & \text { D } & \text { Total } \\\hline \text { Clear } & 27 & 41 & 21 & 7 & 96 \\\text { Return } & 11 & 15 & 9 & 11 & 46 \\\hline \text { Total } & 38 & 56 & 30 & 18 & 142\end{array}\end{array}$$ They will use this information to test for a difference among the proportion of clear operations using a chi-square test with a level of significance of 0.05.
-Referring to Table 12-9, the overall or average proportion of clear operations is_____ .

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Definitions:

Trained Introspection

A method used in early psychology involving trained observers reporting their thoughts and mental processes in response to stimuli.

Subjective

Based on or influenced by personal feelings, tastes, or opinions, rather than external facts or evidence.

Psychological Research

The scientific study of the mind and behavior through experiments, observation, and analysis to understand psychological phenomena.

Structuralism

An approach in psychology that analyzes the basic elements of thoughts and sensations to understand the structure of the mind.