document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=174374>Question 174374</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A coin was flipped 60 times and came up heads 38 times.<BR>\n" );
document.write( " (a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. <BR>\n" );
document.write( "(b) Calculate a p-value and interpret it.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #129343 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=129343\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A coin was flipped 60 times and came up heads 38 times.<BR>\n" );
document.write( "(a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations.<BR>\n" );
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document.write( "Ho: p = 1/2<BR>\n" );
document.write( "Ha: p is not 1/2<BR>\n" );
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document.write( "Critical value for 2-tail test with alpha = 1%: +/- 2.5758..<BR>\n" );
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document.write( "Test statistic: z(28/60) = [(28/60)-0.5]/[0.5*0.5/sqrt(60)] = -1.0328<BR>\n" );
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document.write( "Conclusion: Since TS is not in the rejection interval, Fail to Reject Ho.<BR>\n" );
document.write( "The test provides evidence that the coin is not biased.<BR>\n" );
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document.write( "(b) Calculate a p-value and interpret it.<BR>\n" );
document.write( "P(z<-1.0328) = 0.150845<BR>\n" );
document.write( "Since this is a 2-tail test the p-value is 2(0.150845) or appox. 30%<BR>\n" );
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document.write( "Interpretation: Apporximately 30% of test results could have provided<BR>\n" );
document.write( "stronger evidence for rejecting Ho, i.e. that the coin is biased.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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