Unethical corporate conduct. How complicit are entrylevel accountants in carrying out an unethical request from their superiors? This was the question of interest in a study published in the journal Behavioral Research in Accounting (July 2015). A sample of 86 accounting graduate students participated in the study. After asking the subjects to perform what is clearly an unethical task (e.g., to bribe a customer), the researchers measured each subject’s intention to comply with the unethical request score. Scores ranged from -1.5 (intention to resist the unethical request) to 2.5 (intention to comply with the unethical request). Summary statistics on the 86 scores follow: x¯=2.42,s=2.84.

a. Estimate μ, the mean intention to comply score for the population of all entry-level accountants, using a 90% confidence interval.

b. Give a practical interpretation of the interval, part a.

c. Refer to part a. What proportion of all similarly constructed confidence intervals (in repeated sampling) will contain the true value of μ?

d. Compute the interval, x¯±2s. How does the interpretation of this interval differ from that of the confidence interval, part a?

Short Answer

Expert verified
  1. The 90% confidence interval for the mean intension to comply score for the mean intension to comply score for the population of all entry-level accountsμ lies between 1.916 and 2.924.
  1. There is 90% confident that the mean intention to comply score for the population of all entry-level accountsμ lies between 1.916 and 2.924.
  1. About 90% of all similarly constructed confidence intervals will contain the true value of population meanμ in repeated sampling.
  1. The intervalx¯±2s is 3.26,8.1.

Step by step solution

01

Given information

Sample size n=86, the meanx¯=2.42 and the standard deviation s=2.84.

02

Estimating the mean μ

Here, the confidence coefficient is 0.90. Therefore,

1α=0.90α=0.10α2=0.05

From table, the requiredz0.05value for 90% confidence level is 1.645.

The 90% confidence interval is obtained is obtained below:

x¯±zα2σx¯=2.42±1.6452.8486=2.42±0.504=2.42+0.504,2.4200.504

That is 1.916,2.924

Thus, the 90% confidence interval for the mean intension to comply score for the population of all entry-level accountsμ lies between 1.916 and 2.924.

03

Interpretation

There is 90% confident that the mean intention to comply score for the population of all entry-level accountsμ lies between 1.916 and 2.924.

04

Calculating the proportion

About 90% of all similarly constructed confidence intervals will contain the true value of population meanμ in repeated sampling.

05

Computing the confidence interval

x¯±2s=2.42±22.84=2.42±5.68=2.42+5.68,2.425.68=3.26,8.1

Thus, the interval x¯±2sis 3.26,8.1.

From, part a. the 95% confidence interval provides the range of values for the population mean μ. But, the intervalx¯±2s provides the range of actual values of X.

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