document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=927704>Question 927704</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What decision is reached when 'a' is greater than the p-value? \r<BR>\n" );
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document.write( "When 'a' is greater than the p-value, the null hypothesis is rejected. \r<BR>\n" );
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document.write( "Why is this decision reached? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #563171 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=563171\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a is the critical value in a decision, if i understand the question correctly.<BR>\n" );
document.write( "p is the value that you get from the analysis.<BR>\n" );
document.write( "a is the cutoff value to indicate if the study results are statistically significant or not.<BR>\n" );
document.write( "if p is greater than a, then the results are considered to be possible due to chance variations in each sample, and the null hypothesis cannot be rejected.<BR>\n" );
document.write( "if p is less than a (this is the same as a is greater than p), then the results of the study are considered to not be likely just due to chance variations in each sample, and the null hypothesis is rejected.\r<BR>\n" );
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document.write( "this all depends on the selection of a as the arbitrary cutoff point.\r<BR>\n" );
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document.write( "if a is loose, like maybe = 10%, then it's not as hard to reject the null hypothesis as it would be if a was very strict, like 1%.\r<BR>\n" );
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document.write( "you have a population and you have samples taken from that population.<BR>\n" );
document.write( "if a = 10%, then 90% of the sample means are expected to have a p greater than 10%.<BR>\n" );
document.write( "if a = 1%, then 99% of the sample means are expected to have a p greater than 1%.\r<BR>\n" );
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document.write( "when a = 10% and you get a sample mean that has a p less than 10%, this means that a sample with the same results as this sample is only expected to occur less than 10% of the time.\r<BR>\n" );
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document.write( "obviously, an alpha of 10% is not as strict as an alpha of 1%.\r<BR>\n" );
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document.write( "the choice of alpha is dependent on many factors, and it is critical to the results of the study.\r<BR>\n" );
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document.write( "the choice of alpha is agreed on before the study is performed and the researchers are ethically bound not to change it regardless of the results of the study.\r<BR>\n" );
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document.write( "here's one reference out of many that you can find on the web it you do a search for alpha and p value and the difference between them.\r<BR>\n" );
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document.write( "<a  rel=nofollow HREF= \"http://statistics.about.com/od/Inferential-Statistics/a/What-Is-The-Difference-Between-Alpha-And-P-Values.htm\" target = \"_blank\">http://statistics.about.com/od/Inferential-Statistics/a/What-Is-The-Difference-Between-Alpha-And-P-Values.htm</a>\r<BR>\n" );
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document.write( " </SPAN>\n" );
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