A group of 176 low birth weight children born in Vancouver were cross classified

Question

A group of 176 low birth weight children born in Vancouver were cross classified according to the term of the pregnancy (premature of full term) and the mother's area of residence in Vancouver. What percentage of these births is: i. Premature? ii. Premature and the mother lives downtown? iii. Premature or the mother lives downtown? What percentage of the births to mothers who live downtown is premature? Based on these 176 births, are the term of a pregnancy and the mother's area of residence independent? Carry out a Chi-Square test to test the hypothesis. State the null and alternate hypotheses, give the chi-square value, degrees of freedom, p-value and state your conclusion about the hypotheses.

Explanation / Answer

a)(i))% of premature birth =(121/176)*100 =68.75%

ii) % =(26/176)*100 =14.77%

iii) % =((121+30-26)/176)*100 =71.02%

b)

% of births =(26/30)*100 =86.67%

c)

null hypothesis:term of pregnancy and and mother;s area of residence is independent.

alternate hypothesis:term of pregnancy and and mother;s area of residence is dependent.

applying chi square test of independence on above contingency test:

for above test chi square value =5.615

degree of freedom =(row-1)*(column-1)=(2-1)*(3-1)=2

p value =0.060

as p value is greater then 0.05 level we can not reject null hypothesis.

we do not have sufficient evidence to conclude that term of pregnancy and and mother;s area of residence is dependent.

Observed O Downtown East side South Total Premature 26 39 56 121 full term 4 19 32 55 Total 30 58 88 176 Expected E=rowtotal*column total/grand total Downtown East side South Total Premature 20.625 39.875 60.500 121 full term 9.375 18.125 27.500 55 Total 30 58 88 176 chi square =(O-E)^2/E Downtown East side South Total Premature 1.401 0.0192 0.3347 1.755 full term 3.082 0.042 0.736 3.860 Total 4.482 0.061 1.071 5.615

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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