In: Statistics and Probability
A research group conducted an extensive survey of 2849 wage and salaried workers on issues ranging from relationships with their bosses to household chores. The data were gathered through hour-long telephone interviews with a nationally representative sample. In response to the question, "What does success mean to you?" 1607 responded, "Personal satisfaction from doing a good job." Let p be the population proportion of all wage and salaried workers who would respond the same way to the stated question. Find a 90% confidence interval for p. (Round your answers to three decimal places.)
lower limit
upper limit
SOLUTION:'
Solution :
Given that,
n = 2849
x = 1607
Point estimate = sample proportion = = x / n = 1607 / 2849 =0.564
1 - = 1-0.564=0.436
At 90% confidence level
= 1 - 90%
=1 - 0.90 =0.1
/2
= 0.05
Z/2
= Z0.05 = 1.645
Margin of error = E = Z / 2 * (( * (1 - )) / n)
= 1.645(((0.564*0.436) /2849 )
= 0.015
A 90% confidence interval for p is ,
- E < p < + E
0.564-0.015< p < 0.564+0.015
0.549< p < 0.579
LOWE LIMIT 0.549
UPPER LIMIT 0.579