document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=31328>Question 31328</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help on practical questions relating to chi-squared distribution:-\r<BR>\n" );
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document.write( "60 male and 50 female students at school. Each had to choose after-school activity from football,tennis,badmington and athletics. 25 males and 10 females picked football, only 3 males decided on tennis and 14 for badmington. Rest of males chose athletics along with 30 females. Remainder of females chose tennis and badminton in equal measure.\r<BR>\n" );
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document.write( "a)write down observed and expected frequency tables<BR>\n" );
document.write( "b)write down null and alternative hypothesis to test wether sex and activity related<BR>\n" );
document.write( "c)carry out chi squared distribution test at 5% significance level to test above hypothesis </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #18058 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=18058\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You get two rows: male and female:<BR>\n" );
document.write( "Columns left to right are football, tennis, badminton, athletics<BR>\n" );
document.write( "Observed values for males are 25, 3,  14,  18 to total 60<BR>\n" );
document.write( "Observed values for girls are 10, 5,   5,  30 to total 50\r<BR>\n" );
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document.write( "Expected values follow the formula (row total)(column total)/(grand total)<BR>\n" );
document.write( "So corresponding to the \"25\" box you have (60)(35)/110= 19.09\r<BR>\n" );
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document.write( "Do that for each of the eight boxes to get all the expected values.\r<BR>\n" );
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document.write( "The null hypothesis is \"The rows are homogeneous\"<BR>\n" );
document.write( "The altermate is \"The rows are not homogeneous\".\r<BR>\n" );
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document.write( "Using a TI-83 Chi-Sq. Test I get Chi-Sq.= 13.3933...<BR>\n" );
document.write( "and p=0.003\r<BR>\n" );
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document.write( "Since 0.003<5% we reject the null hypothesis and conclude<BR>\n" );
document.write( "that sex does play a factor in what games people choose<BR>\n" );
document.write( "to sign up for.\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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document.write( "Since <BR>\n" );
document.write( " </SPAN>\n" );
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