document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=126171>Question 126171</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0072966939/algebrahomeworkh>Applied Statistics in Business and Economics</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Please provide some assistance in solving and understanding this statistics problem. Thanks in advance for your help! <BR>\n" );
document.write( "Does lovastatin (a cholesterol-lowering drug) reduce the risk of heart attack? In a Texas study, researchers gave lovastatin to 2,325 people and an inactive substitute to 2,081 people (average age 58). After 5 years, 57 of the lovastatin group had suffered a heart attack, compared with 97 for the inactive pill. (a) State the appropriate hypotheses. (b) Obtain a test statistic and p-value. Interpret the results at a .01 level of significance. (c) Is normality assured? (d) Is the difference large enough to be important? (e) What else would medical researchers need to know before prescribing this drug widely? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #92471 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=92471\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Does lovastatin (a cholesterol-lowering drug) reduce the risk of heart attack? In a Texas study, researchers gave lovastatin to 2,325 people and an inactive substitute to 2,081 people (average age 58). After 5 years, 57 of the lovastatin group had suffered a heart attack, compared with 97 for the inactive pill. (a) State the appropriate hypotheses.<BR>\n" );
document.write( "Ho: p(placebo)-p(medicated) > 0<BR>\n" );
document.write( "Ha: p(placebo)-p(medicated) <=0<BR>\n" );
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document.write( "x(placebo)=97 ; n(placebo)=2081 ;  p-hat(placebo) = 0.0466<BR>\n" );
document.write( "x(medicated)=57 ; n(medicated)=2325 ; p-hat(medicated) = 0.0245<BR>\n" );
document.write( "Critical value for alph=0.01 = 2.326<BR>\n" );
document.write( "Test statistic: z=3.9868 <BR>\n" );
document.write( "p-value = 3.34*10^-5\r<BR>\n" );
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document.write( " (b) Obtain a test statistic and p-value. Interpret the results at a .01 level of significance.<BR>\n" );
document.write( "Reject Ho.<BR>\n" );
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document.write( "(c) Is normality assured?<BR>\n" );
document.write( "Check n1p1>5 and n2p2>5<BR>\n" );
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document.write( " (d) Is the difference large enough to be important?<BR>\n" );
document.write( "Yes, the low p-value shows the evidence is very strong that the <BR>\n" );
document.write( "medicine is effective.<BR>\n" );
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document.write( " (e) What else would medical researchers need to know before prescribing this drug widely?<BR>\n" );
document.write( "I'll leave that to you.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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