Ochsenkuhn et al A33 studied birth as a result of in vitro f

Ochsenk€uhn et al. (A-33) studied birth as a result of in vitro fertilization (IVF) and birth from spontaneous conception. In the sample, there were 163 singleton births resulting from IVF with a mean birth weight of 3071g and sample standard deviation of 761g. Among the 321 singleton births resulting from spontaneous conception, the mean birth weight was 3172 g with a standard deviation of 702g. Determine if these data provide sufficient evidence for us to conclude that the mean birth weight in grams of singleton births resulting from IVF is lower, in general, than the mean birth weight of singleton births resulting from spontaneous conception. Let a alpha = 0.10.

Solution

Set Up Hypothesis
Null Hypothesis , There Is No-Significance between them Ho: u1 > u2
Alternate, mean birth weight resulting from IVF is lower - H1: u1 < u2
Test Statistic
X(Mean)=3071
Standard Deviation(s.d1)=761 ; Number(n1)=163
Y(Mean)=3172
Standard Deviation(s.d2)=702; Number(n2)=321
we use Test Statistic (t) = (X-Y)/Sqrt(s.d1^2/n1)+(s.d2^2/n2)
to =3071-3172/Sqrt((579121/163)+(492804/321))
to =-1.42
| to | =1.42
Critical Value
The Value of |t | with Min (n1-1, n2-1) i.e 162 d.f is 1.287
We got |to| = 1.41594 & | t | = 1.287
Make Decision
Hence Value of | to | > | t | and Here we Reject Ho
P-Value:Left Tail - Ha : ( P < -1.4159 ) = 0.07936
Hence Value of P0.1 > 0.07936,Here we Reject Ho

conclude that the mean birth weight in grams of singleton
births resulting from IVF is lower