document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=182826>Question 182826</A>: <I><SPAN STYLE=\"word-break: break-all;\"> High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound meter. Noise level is defined as “Low” (under 88 decibels), “Medium” (88 to 91 decibels), or “High” (92 decibels or more). There are three flight phases (Climb, Cruise, Descent). Research question: At &#945; = .05, is the cockpit noise level independent of flight phase\r<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 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #137371 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=137371\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound meter. Noise level is defined as “Low” (under 88 decibels), “Medium” (88 to 91 decibels), or “High” (92 decibels or more). There are three flight phases (Climb, Cruise, Descent). Research question: At &#945; = .05, is the cockpit noise level independent of flight phase <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( "Ho: row and column factors are independent<BR>\n" );
document.write( "Ha: they are dependent<BR>\n" );
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document.write( "I ran a Chi-Sq. Test on the 3 by 3 array of data.<BR>\n" );
document.write( "Test Statistic: Chi-Sq. = 15.160<BR>\n" );
document.write( "p-value: 0.004<BR>\n" );
document.write( "df: (3-1)(3-1) = 4<BR>\n" );
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document.write( "Conclusion:<BR>\n" );
document.write( "Since p-value is less than 5%, Reject Ho.<BR>\n" );
document.write( "The row and column factors are dependent.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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