Purchase Solution

Two proportions

Not what you're looking for?

Ask Custom Question

Some defendants in criminal proceedings plead guilty and are sentenced without a trial, whereas others who plead innocent are subsequently found guilty and then are sentenced. In recent years, legal scholars have speculated as to whether sentences of those who plead guilty differ in severity from sentences for those who plead innocent and are subsequently judged guilty. Consider the data given below on defendants accused of robbery, all of whom, by the way, had previous prison records. At the .01 level of significance, do these data suggest that the proportion of all defendants in these circumstances who plead guilty and are sent to prison differs from the proportion who are sent to prison after pleading innocent and being found guilty?

Plea
Guilty Not Guilty
Number judged guilty n1 = 191 n2 = 64
Number sentenced to prison x1 = 101 x2 = 56
Sample proportion P1 = .529 p2 = .875

A. No, because the test value -1.96 is inside the interval (-2.58, 2.58)
B. No, because the test value -4.94 is outside the interval (-1.96, 1.96)
C. Yes, because the test value -4.94 is outside the interval (-2.58, 2.58)
D. Yes, because the test value 2.58 is inside the interval (-4.94, 4.94)

Purchase this Solution
Solution Summary

The solution provides step by step method for the calculation of confidence interval for two proportions . Formula for the calculation and Interpretations of the results are also included.

Purchase this Solution
Free BrainMass Quizzes
Know Your Statistical Concepts

Each question is a choice-summary multiple choice question that presents you with a statistical concept and then 4 numbered statements. You must decide which (if any) of the numbered statements is/are true as they relate to the statistical concept.

Measures of Central Tendency

This quiz evaluates the students understanding of the measures of central tendency seen in statistics. This quiz is specifically designed to incorporate the measures of central tendency as they relate to psychological research.

Terms and Definitions for Statistics

This quiz covers basic terms and definitions of statistics.

Measures of Central Tendency

Tests knowledge of the three main measures of central tendency, including some simple calculation questions.

View More Free Quizzes
Related BrainMass Solutions

  • Hypothesis Testing of Proportions

    In Scotland, 39 of 179 patients had two or more drugs prescribed. Test the null hypothesis of equal proportions giving the resulting p- value. Construct a 95% confidence interval for the difference in proportions.

  • Z test for two population proportions

    310024 Z test for two population proportions A clinical trial is conducted comparing a new pain reliever for arthritis to a placebo.

  • Comparing Two Population Proportions

    244110 Comparing Two Population Proportions Which of the following examples illustrates a study that compares two population proportions? a. The amount of saliva secreted daily by men and women. b.

  • Z test for population proportions

    H0: There is no significant difference in the proportions of defective disks from the two suppliers. H1: There is significant difference in the proportions of defective disks from the two suppliers.

  • Statistics - One Sample t-test

    test for proportions one-sample z confidence interval for proportions two-sample z test for proportions two-sample z confidence interval for proportions Remember to state your question clearly, state Ho and Ha.

  • Z-Test

    459497 Testing the Difference: Two Means, Proportions and Variances Please provide assistance in getting this z-test done. The chapter has to do with testing the difference between two means, two proportions, and two variances.

  • Finding the confidence interval for two proportions

    The solution gives detailed steps on finding the confidence interval for two proportions and then analyzing the result.

  • Testing of hypothesis

    194721 Sample proportions and test statistic for equal proportions Find the sample proportions and test statistic for equal proportions. Is the decision close? Find the p-value. a.

  • Standard Error for Difference in Proportion

    327597 Calculate the standard error for the difference between two proportions When testing the difference between two proportions, one sample had 30 out of 100 who were for capital punishment and the other sample had 60 out of 80 who were for capital

  • Null and Alternative hypothesis

    A)No, there is not sufficient information to reject the hypothesis that the proportions of students at the two schools who have ear infections are the same because the test value -1.78 is inside the acceptance region (-1.96,1.96).

View More Related Solutions