document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=971704>Question 971704</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A neurologist is testing the effect of a drug on response times by injecting 100 rats, subjecting each to a neurological stimulus. The mean of the response time for the rejected rats is 1.05 seconds with standard deviation of 0.5 seconds. The neurologist knows that the mean response time for rats NOT injected with the drug is 1.2 seconds. Does the drug have an effecton response time?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #594111 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=594111\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ho=no difference<BR>\n" );
document.write( "Ha=difference<BR>\n" );
document.write( "alpha =0.05 P{effect|no effect} P reject null hypothesis and shouldn't. Assume normally distributed.<BR>\n" );
document.write( "test statistic is z (n=100) <BR>\n" );
document.write( "Critical value is |z|>1.96, given that they are asking for an effect and not for a directional one.\r<BR>\n" );
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document.write( "z= (1.05-1.2)/).5/sqrt (100)\r<BR>\n" );
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document.write( "z=-0.15/(.5/10)  =  0.15/0.05 =3\r<BR>\n" );
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document.write( "Reject null hypothesis since |z| > 1.96\r<BR>\n" );
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document.write( "There is strong evidence that the drug has an effect.   </SPAN>\n" );
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