document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=293251>Question 293251</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 9.22 The mean arrival rate of flights at O’Hare Airport in marginal weather is 195 flights per hour with a historical standard deviation of 13 flights. To increase arrivals, a new air traffic control procedure is implemented. In the next 30 days of marginal weather the mean arrival rate is 200 flights per hour. (a) Set up a right-tailed decision rule at a =.025 to decide whether there has been a significant increase in the mean number of arrivals per hour. (b) Carry out the test and make the decision. Is it close? Would the decision be different if you used a = .01? (c) What assumptions are you making,<BR>\n" );
document.write( "if any? Flights\r<BR>\n" );
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document.write( "210 215 200 189 200 213 202 181 197 199<BR>\n" );
document.write( "193 209 215 192 179 196 225 199 196 210<BR>\n" );
document.write( "199 188 174 176 202 195 195 208 222 221<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 #211739 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=211739\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The mean arrival rate of flights at O’Hare Airport in marginal weather <BR>\n" );
document.write( "is 195 flights per hour with a historical standard deviation of 13 flights. <BR>\n" );
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document.write( "To increase arrivals, a new air traffic control procedure is implemented.<BR>\n" );
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document.write( " In the next 30 days of marginal weather the mean arrival rate is 200 flights per hour. <BR>\n" );
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document.write( "(a) Set up a right-tailed decision rule at a =.025 to decide whether there has been a significant increase in the mean number of arrivals per hour. <BR>\n" );
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document.write( "(b) Carry out the test and make the decision. Is it close? Would the decision be different if you used a = .01? <BR>\n" );
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document.write( "(c) What assumptions are you making, if any? <BR>\n" );
document.write( "Flights <BR>\n" );
document.write( "210 215 200 189 200 213 202 181 197 199<BR>\n" );
document.write( "193 209 215 192 179 196 225 199 196 210<BR>\n" );
document.write( "199 188 174 176 202 195 195 208 222 221<BR>\n" );
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document.write( "Ho: u =195<BR>\n" );
document.write( "Ha: u > 195<BR>\n" );
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document.write( "test statistic: t(200) = (200-195)/[13/sqrt(30)] = 2.1066..<BR>\n" );
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document.write( "p-value = tcdf(2.1066,100, with df = 29) = 0.022<BR>\n" );
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document.write( "Conclusion: Since the p-value is less than 0.025 reject Ho.<BR>\n" );
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document.write( "Yes, the decision is close.<BR>\n" );
document.write( "Yes, the decision would be to not reject Ho if alpha was 1%<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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