Two Surgical Procedures Are Widely Used to Treat a Certain

question 82

Essay

Two surgical procedures are widely used to treat a certain type of cancer. To compare the success rates of the two procedures, random samples of surgical patients were obtained and the numbers of patients who showed no recurrence of the disease after a 1-year period were recorded. The data are shown in the table. $$\begin{array} { l c c } \hline & n & \text { Number of Successes } \\\hline \text { Procedure A } & 100 & 83 \\\text { Procedure B } & 100 & 81 \\\hline\end{array}$$ How large a sample would be necessary in order to estimate the difference in the true success rates to within .10 with 95% reliability?

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Definitions:

Degrees of Freedom

The number of values in the final calculation of a statistic that are free to vary.

Null Hypothesis

A hypothesis that asserts there is no significant difference or effect and serves as the default assumption to be tested against an alternative hypothesis.

Chi-square Statistic

A statistical test used to determine if there's a significant difference between observed frequencies and expected frequencies in categorical data.

Degrees of Freedom

The number of independent pieces of information used in the calculation of a statistic, often associated with the complexity of the data.