document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1180805>Question 1180805</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A principal wants to know if the students at her school like the food served in the cafeteria, so she asks the<BR>\n" );
document.write( "first 25 students in the line at lunch. Identify the type of sample and describe the population. Then tell if the<BR>\n" );
document.write( "sample is biased. Explain. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #810600 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=810600\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It is biased because not everybody in the population has a defined non-zero probability of being chosen.  If some students can't possibly be in the first 25, their probability is not some non-zero value (even if very small). It is zero.  Better to choose every third (second, fourth, whatever) student.\r<BR>\n" );
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document.write( "This is a convenience sample. The population is all the students in the school. The sample is biased. The explanation is above. </SPAN>\n" );
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