document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=139745>Question 139745</A>: <I><SPAN STYLE=\"word-break: break-all;\"> There is no answer associated with the question below posted but is showing as answered in the que.  Please help!\r<BR>\n" );
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document.write( "Question 139208: High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this<BR>\n" );
document.write( "hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld<BR>\n" );
document.write( "sound meter. Noise level is defined as “Low” (under 88 decibels), “Medium” (88 to 91 decibels), <BR>\n" );
document.write( "or “High” (92 decibels or more). There are three flight phases (Climb, Cruise, Descent). Research<BR>\n" );
document.write( "question: At &#945; = .05, is the cockpit noise level independent of flight phase? (Data are from Capt. Robert E. Hartl, retired.) Noise<BR>\n" );
document.write( "Noise Level Climb Cruise Descent Row Total<BR>\n" );
document.write( "Low 6 2 6 14<BR>\n" );
document.write( "Medium 18 3 8 29<BR>\n" );
document.write( "High 1 3 14 18<BR>\n" );
document.write( "Col Total 25 8 28 61 <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 #101932 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=101932\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> High level of cockpit noise in an aircraft can damage hearing of pilots who are exposed to this hazard for many hours. A Beoing 727 co-pilot collected 61 noise observations using a handled sound meter. Noise level is defined as \"low (under 88 decibles), Medium (88 to 91), high (92 or more). There are three flight phases (Climb,Cruise,Descent). At alph=.05, is the cockpit noise level independent of flight phase? <BR>\n" );
document.write( "State hypothesis<BR>\n" );
document.write( "Ho: noise and flight phase are independent<BR>\n" );
document.write( "Ha: they are dependent<BR>\n" );
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document.write( "show degrees of freedom<BR>\n" );
document.write( "(# of rows -1)(# of columns -1) = (2)(2) = 4<BR>\n" );
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document.write( "find critical value of chisquare<BR>\n" );
document.write( "Chi-Sq critical values for 2-tail Chi-Sq. Test: 0.484 and 11.143<BR>\n" );
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document.write( "interpret p=value<BR>\n" );
document.write( "p-value is 0.0044<BR>\n" );
document.write( "Only 0.0044 of test results would show stronger evidence for rejecting Ho.<BR>\n" );
document.write( "Since p-value is less than 5%, reject Ho.<BR>\n" );
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document.write( "Noise Level,Climb,Cruise,Descent,Row Total<BR>\n" );
document.write( "Low,6,2,6,14<BR>\n" );
document.write( "Medium,18,3,8,29<BR>\n" );
document.write( "High,1,3,14,18<BR>\n" );
document.write( "Col total,25,8,28,61<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. <BR>\n" );
document.write( " \r<BR>\n" );
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