3. email and privacy. A survey of 436 workers showed that 192 of the said that it was seriously unethical to monitor employee e-mail. when 121 senior-level bosses were surveyed 40 said that it was seriosly unethical to monitor employee email ( based on data from a gallup poll) Use a 0.05 significance level to test the claim that for those saying that monitoring email is seriously unethical the proportion of employees is greater than the proportion of bosses.
Ho:
Ha:
mean: .05
Rejection Region:
Calc=2.17
Formula is:
Rejection Ho or cannot Reject Ho ( which one)
Is the proportion of workers greater than the proportion of bosses?
P value?
Third question stats hw math?
These surveys have yes/no (two categorical) answers, so
it's an example of a binomial experiment.
These binomial distributions, with fairly large samples, can be approximized by a normal distribution N(np , sqrt(npq)), with these surveys we have
workers answers : p= 192/436 = 0.44, q = 1-p = 0.56
X ~ N(192,sqrt(0.44*0.56*436) = N ( 192, 107.4 )
Bosses answers : p = 40/121 = 0.33 ; q = 1-p = 0.67
Y ~ N(40, 0.33*0.67*120) = N (40, 26.75).
We can now test on equal means with the Student-t test:
T1 = Sqrt ( (n1*n2*(n1+n2-2)/(n1+n2))
T2 = (m_x - m_y)/ sqrt((n1-1)*s²_x + (n2-1)*s²_y )
T0 = T1*T2 = 2.17 (you say)
The solution c of the equation p(T%26gt;c)=0.95 can be read from the table of the Student-t-distribution with (n1+n2-2)=555 d.f.
Giving c = 1.65.
Because T0 = 2.17 %26gt; 1.96 we reject the null hypothesis of equal means in favour of a significant difference of opinion.
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