document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=260070>Question 260070</A>: <I><SPAN STYLE=\"word-break: break-all;\"> two groups of patients were given. eight in each group. the mean and standard deviation of both groups given. \r<BR>\n" );
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document.write( "carry out a formal test of hypothesis that the population means are the same. what assumptions are required for this test.\r<BR>\n" );
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document.write( "obtain a 95% confidence interval for the difference between population means\r<BR>\n" );
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document.write( "plz tell how to do this </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #191498 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=191498\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> patients undergoing bypass surgery were randomised into one of the two groups.<BR>\n" );
document.write( "Group 1 - received a 50% nitrous oxide and 50% oxygen mixture continously for 24 hrs<BR>\n" );
document.write( "Group 2 - received a 50 % notrous oxide and 50% oxygen only during the operation\r<BR>\n" );
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document.write( "table shows red cell folate levels for grous 24 hrs later\r<BR>\n" );
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document.write( "group 1                 group 2<BR>\n" );
document.write( "243                        206<BR>\n" );
document.write( "251                        210<BR>\n" );
document.write( "275                        226<BR>\n" );
document.write( "291                        249 <BR>\n" );
document.write( "347                        255  <BR>\n" );
document.write( "354                        273  <BR>\n" );
document.write( "380                        285 <BR>\n" );
document.write( "392                        295 <BR>\n" );
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document.write( "mean 316.6                 249.9  <BR>\n" );
document.write( "SD 58.7                      33.6\r<BR>\n" );
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document.write( "carry out a formal test of hypothesis that the population means are the same. what assumptions are required for the test<BR>\n" );
document.write( "Ho: u1-u2 = 0<BR>\n" );
document.write( "Ha: u1-u2 is not 0<BR>\n" );
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document.write( "I ran a 2-Sample Ttest on a TI calculator and got the following:<BR>\n" );
document.write( "test statistic: t = 2.78928...<BR>\n" );
document.write( "p-value = 2*P(t > 2.78928,df = n1+n2-2 = 14) = 0.01742<BR>\n" );
document.write( "(The calculator came up with df = 11.14234...)<BR>\n" );
document.write( "Conclusion: Based on the p-value, reject Ho at the 1% significance level,<BR>\n" );
document.write( "or fail to reject Ho at the 5% significance level.<BR>\n" );
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document.write( "obtain a 95% confidence interval for the difference between the population means<BR>\n" );
document.write( "I ran a 2-Sample TInterval and got the following:<BR>\n" );
document.write( "14.15 < u1-u2 < 119.25<BR>\n" );
document.write( "These results based on:<BR>\n" );
document.write( "sample mean difference: 316.6-249.9 = 66.7<BR>\n" );
document.write( "sample standard error = (1/2)(119.25-14.15) = 52.66<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "discuss the relationship between the two above.\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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