Find the critical value Z_alpha/2 that corresponds to a 99.5% confidence level.

Question

Find the critical value Z_alpha/2 that corresponds to a 99.5% confidence level. First determine alpha (1-.995), then determine alpha/2 and find the area under the curve (1-alpha/2): use Table A-2 to determine Z_alpha/2. Z_alpha/2 = Find Z_alpha/2 for alpha =0.02 First find alpha/2, then the area under the curve 1- alpha/2. Use the area under the curve in Table A-2 to determine z_alpha/2. Z_alpha/2 = Find the margin of error E that corresponds to the given statistics and confidence levels, 90% confidence; x = 623, the sample size n = 1780: of which 35% are successes (p = .35). E = z_alpha/2 squareroot pq/n E =

Explanation / Answer

1) = 1 - 0.995 = 0.005

/2 = 0.0025

Z/2 = 2.81

b) = 0.02

/2 = 0.01

Z/2 = 2.33

c) p = 0.35

q = 1 - p = 0.65

n = 1780

= 1 - 0.9 = 0.1

/2 = 0.05

Z/2 = 1.645

E = Z/2 * sqrt(p * q / n) = 1.645 * sqrt(0.35 * 0.65 / 1780) = 0.0186

Related Questions

Navigate

• Browse (All)
• Browse F
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.