5. Claire wants to see if people in the US and Canada differ in their salt intak

Question

5. Claire wants to see if people in the US and Canada differ in their salt intakes. She takes a sample of Nys = 150 and NCAN = 100 adults and surveys them on their eating behavior. She finds that the averages (in grams) for the two groups are Fus 3.55 and tCAN 3.4. The sample variances for 82s = l and 82AN-08. Given this information, can she say that there is a statistical difference (at the 10%, 5%, or 1% levels) in salt intake between the US and Canada? Round all of your relevant values to three decimals]

Explanation / Answer

Here if we mark US as 1 and CANADA as 2

so N1 = 150 ; N2 = 100

x1 = 3.55 ; x2 = 3.4

s12 =1 ; s22 = 0.8

Pooled standard diiference sp = sqrt [{(n1 -1)s12 + (n2 -1)s22}/(n1 + n2 -2)]

= sqrt [{(149 * 1 + 99 * 0.8)/ (149 + 99)] = 0.95925

Standard error of difference se0 = sp * sqrt[1/n1 + 1/n2] = 0.95925 * sqrt(1/150 + 1/100) = 0.124

Test statistics

t = (x1 -x2)/ se0 = (3.55 - 3.4)/0.124 = 1.211

Here p - value = 2 * Pr(t < 1.211 ; dF = 150 + 100 - 2) = 0.2269

so here we can say that p - value is higher than all the mentioned statistical difference level 0.10, 0.05 and 0.01 so we can say that there is no statistical difference in salt intake between US and the Canada citizens

Related Questions

Navigate

• Browse (All)
• Browse 5
• Subjects

---

---

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