document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=139310>Question 139310</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need desperate help on this problem....\r<BR>\n" );
document.write( "\n" );
document.write( "A manager hopes to improve the sales figures for 10 employees by sending them to a motivational seminar.  To test the effectiveness of this seminar, the manager compares the sales figures for each salesperson for the month immediately prior to the seminar and the month immediately following it.  \r<BR>\n" );
document.write( "\n" );
document.write( "Employee                <BR>\n" );
document.write( "Homer               <BR>\n" );
document.write( "Bart <BR>\n" );
document.write( "Lisa<BR>\n" );
document.write( "Marge<BR>\n" );
document.write( "Maggie<BR>\n" );
document.write( "Ned<BR>\n" );
document.write( "Milhouse<BR>\n" );
document.write( "Willie<BR>\n" );
document.write( "Stu<BR>\n" );
document.write( "Gill\r<BR>\n" );
document.write( "\n" );
document.write( "Before<BR>\n" );
document.write( "19<BR>\n" );
document.write( "6<BR>\n" );
document.write( "9<BR>\n" );
document.write( "5<BR>\n" );
document.write( "9<BR>\n" );
document.write( "8<BR>\n" );
document.write( "11<BR>\n" );
document.write( "11<BR>\n" );
document.write( "11<BR>\n" );
document.write( "7\r<BR>\n" );
document.write( "\n" );
document.write( "After<BR>\n" );
document.write( "12<BR>\n" );
document.write( "18<BR>\n" );
document.write( "12<BR>\n" );
document.write( "7<BR>\n" );
document.write( "14 <BR>\n" );
document.write( "17<BR>\n" );
document.write( "9<BR>\n" );
document.write( "17<BR>\n" );
document.write( "12<BR>\n" );
document.write( "7\r<BR>\n" );
document.write( "\n" );
document.write( "Run a statistical hypothesis test and determine if the seminar significantly improved sales figures for the company.  <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #101581 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=101581\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A manager hopes to improve the sales figures for 10 employees by sending them to a motivational seminar.  To test the effectiveness of this seminar, the manager compares the sales figures for each salesperson for the month immediately prior to the seminar and the month immediately following it.  \r<BR>\n" );
document.write( "\n" );
document.write( "Employee                <BR>\n" );
document.write( "Homer               <BR>\n" );
document.write( "Bart <BR>\n" );
document.write( "Lisa<BR>\n" );
document.write( "Marge<BR>\n" );
document.write( "Maggie<BR>\n" );
document.write( "Ned<BR>\n" );
document.write( "Milhouse<BR>\n" );
document.write( "Willie<BR>\n" );
document.write( "Stu<BR>\n" );
document.write( "Gill\r<BR>\n" );
document.write( "\n" );
document.write( "Before<BR>\n" );
document.write( "19<BR>\n" );
document.write( "6<BR>\n" );
document.write( "9<BR>\n" );
document.write( "5<BR>\n" );
document.write( "9<BR>\n" );
document.write( "8<BR>\n" );
document.write( "11<BR>\n" );
document.write( "11<BR>\n" );
document.write( "11<BR>\n" );
document.write( "7\r<BR>\n" );
document.write( "\n" );
document.write( "After<BR>\n" );
document.write( "12<BR>\n" );
document.write( "18<BR>\n" );
document.write( "12<BR>\n" );
document.write( "7<BR>\n" );
document.write( "14 <BR>\n" );
document.write( "17<BR>\n" );
document.write( "9<BR>\n" );
document.write( "17<BR>\n" );
document.write( "12<BR>\n" );
document.write( "7\r<BR>\n" );
document.write( "\n" );
document.write( "Run a statistical hypothesis test and determine if the seminar significantly improved sales figures for the company.  <BR>\n" );
document.write( "--------------------<BR>\n" );
document.write( "You have before and after data for 10 employees.<BR>\n" );
document.write( "These are dependent data pairs.<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "Find the list of data differences (after-before).<BR>\n" );
document.write( "Find the sum of those differences.<BR>\n" );
document.write( "Find the mean(ud) and standard deviation(sd) of the set of differences.<BR>\n" );
document.write( "------<BR>\n" );
document.write( "Ho: ud = 0<BR>\n" );
document.write( "Ha: ud > 0<BR>\n" );
document.write( "---------------<BR>\n" );
document.write( "Run a T-test on the sample mean (ud)<BR>\n" );
document.write( "Critical value for one-tail t-test with alpha=5% and df=9: t=1.833<BR>\n" );
document.write( "test statistic: t(2.9) = (2.9-0)/[5.466/sqrt(10)]= 1.6778<BR>\n" );
document.write( "------------------<BR>\n" );
document.write( "Conclusion: Since test statistic is not in the rejection interval,<BR>\n" );
document.write( "Fail to reject Ho. The seminar is not increase sales.<BR>\n" );
document.write( "=======================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );