document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=146065>Question 146065</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Has the cost to outsource a standard employee background check changed from 2005 to 2006? A random sample of 10 companies in spring 2005 showed a sample average of $105 with a sample standard deviation equal to $32. A random sample of 10 different companies in spring 2006 resulted in a sample average of $75 with a sample standard deviation equal to $45. (a) Conduct a hypothesis test to test the difference in sample means with a level of significance equal to .05. Assume the population variances are not equal. (b) Discuss why a paired sample design might have made more sense in this case. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #106637 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=106637\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Has the cost to outsource a standard employee background check changed from 2005 to 2006? A random sample of 10 companies in spring 2005 showed a sample average of $105 with a sample standard deviation equal to $32. A random sample of 10 different companies in spring 2006 resulted in a sample average of $75 with a sample standard deviation equal to $45. <BR>\n" );
document.write( "(a) Conduct a hypothesis test to test the difference in sample means with a level of significance equal to .05. Assume the population variances are not equal.<BR>\n" );
document.write( "Ho: means are the same<BR>\n" );
document.write( "Ha: means are not the same<BR>\n" );
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document.write( "I ran a 2-Sample T-test on a TI calculator and got the following:<BR>\n" );
document.write( "t = 1.7181<BR>\n" );
document.write( "p-value = 0.1047<BR>\n" );
document.write( "Conclusion: Since p-value is greater than 5%, fail to reject Ho.<BR>\n" );
document.write( "The means are statistically the same.<BR>\n" );
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document.write( " <BR>\n" );
document.write( "(b) Discuss why a paired sample design might have made more sense in this case.<BR>\n" );
document.write( "It wouldn't because the two samples are independent.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );