📄 m14 - reading sas data sets - 31 of 32.mht
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above<!-- InstanceEndEditable --></TD></TR></TBODY></TABLE>
<P></P>
<LI><!-- InstanceBeginEditable name=3D"q3text" -->Which of the =
following=20
statements is <STRONG>false</STRONG> about BY-group processing?=20
<P>When you use the BY statement with the SET statement: <!-- =
InstanceEndEditable -->
<P>
<TABLE border=3D0>
<TBODY>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Da name=3Dques3> </TD>
<TD> <EM>a.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q3a" -->The data sets =
listed=20
in the SET statement must be indexed or sorted by the =
values of=20
the BY variable(s).<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Db name=3Dques3> </TD>
<TD> <EM>b.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q3b" -->The DATA step =
automatically creates two variables, <CODE>FIRST.</CODE> =
and=20
<CODE>LAST.</CODE>, for each variable in the BY =
statement.<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dc name=3Dques3> </TD>
<TD> <EM>c.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q3c" =
--><CODE>FIRST.</CODE>=20
and <CODE>LAST.</CODE> identify the first and last =
observation in=20
each BY group, respectively.<!-- InstanceEndEditable =
--></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dd name=3Dques3> </TD>
<TD> <EM>d.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q3d" =
--><CODE>FIRST.</CODE>=20
and <CODE>LAST.</CODE> are stored in the data set.<!-- =
InstanceEndEditable --></TD></TR></TBODY></TABLE>
<P></P>
<LI><!-- InstanceBeginEditable name=3D"q4text" -->There are 500=20
observations in the data set <STRONG>Getobs5</STRONG>. What is =
the=20
result of submitting the following program? <PRE><FONT =
color=3D#003399>data work.getobs5(drop=3Dobsnum);</FONT>
<FONT color=3D#003399>obsnum=3D5;</FONT>
<FONT color=3D#003399>set company.usa(keep=3Dmanager payroll) =
point=3Dobsnum;</FONT>
<FONT color=3D#003399>stop;</FONT>
<FONT color=3D#003399>run;</FONT></PRE><!-- InstanceEndEditable -->
<P>
<TABLE border=3D0>
<TBODY>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Da name=3Dques4> </TD>
<TD> <EM>a.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q4a" -->an error<!-- =
InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Db name=3Dques4> </TD>
<TD> <EM>b.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q4b" -->an empty data =
set<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dc name=3Dques4> </TD>
<TD> <EM>c.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q4c" -->a continuous =
loop<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dd name=3Dques4> </TD>
<TD> <EM>d.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q4d" -->a data set =
that=20
contains one=20
observation<!-- InstanceEndEditable =
--></TD></TR></TBODY></TABLE>
<P></P>
<LI><!-- InstanceBeginEditable name=3D"q5text" -->There is no =
end-of-file=20
condition when you use direct access to read data, so how can =
your=20
program prevent a continuous loop?<!-- InstanceEndEditable -->=20
<P>
<TABLE border=3D0>
<TBODY>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Da name=3Dques5> </TD>
<TD> <EM>a.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q5a" -->Do not use a =
POINT=3D=20
variable.<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Db name=3Dques5> </TD>
<TD> <EM>b.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q5b" -->Check for an =
invalid=20
value of the POINT=3D variable.<!-- InstanceEndEditable =
--></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dc name=3Dques5> </TD>
<TD> <EM>c.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q5c" -->Do not use an =
END=3D=20
variable.<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dd name=3Dques5> </TD>
<TD> <EM>d.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q5d" -->Include an =
OUTPUT=20
statement.<!-- InstanceEndEditable =
--></TD></TR></TBODY></TABLE>
<P></P>
<LI><!-- InstanceBeginEditable name=3D"q6text" -->Assuming that =
the data=20
set <STRONG>Company.USA</STRONG> has five or more observations, =
what is=20
the result of submitting the following program? <PRE><FONT =
color=3D#003399>data work.getobs5(drop=3Dobsnum);</FONT>
<FONT color=3D#003399>obsnum=3D5;</FONT>
<FONT color=3D#003399>set company.usa(keep=3Dmanager payroll) =
point=3Dobsnum;</FONT>
<FONT color=3D#003399>output;</FONT>
<FONT color=3D#003399>stop;</FONT>
<FONT color=3D#003399>run;</FONT></PRE><!-- InstanceEndEditable -->
<P>
<TABLE border=3D0>
<TBODY>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Da name=3Dques6> </TD>
<TD> <EM>a.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q6a" -->an error<!-- =
InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Db name=3Dques6> </TD>
<TD> <EM>b.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q6b" -->an empty data =
set<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dc name=3Dques6> </TD>
<TD> <EM>c.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q6c" -->a continuous =
loop<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dd name=3Dques6> </TD>
<TD> <EM>d.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q6d" -->a data set =
that=20
contains one=20
observation<!-- InstanceEndEditable =
--></TD></TR></TBODY></TABLE>
<P></P>
<LI><!-- InstanceBeginEditable name=3D"q7text" -->Which of the =
following=20
statements is <STRONG>true</STRONG> regarding direct access of =
data=20
sets?<!-- InstanceEndEditable -->=20
<P>
<TABLE border=3D0>
<TBODY>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Da name=3Dques7> </TD>
<TD> <EM>a.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q7a" -->You cannot =
specify=20
END=3D with POINT=3D.<!-- InstanceEndEditable =
--></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Db name=3Dques7> </TD>
<TD> <EM>b.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q7b" -->You cannot =
specify=20
OUTPUT with POINT=3D.<!-- InstanceEndEditable =
--></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dc name=3Dques7> </TD>
<TD> <EM>c.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q7c" -->You cannot =
specify=20
STOP with END=3D.<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dd name=3Dques7> </TD>
<TD> <EM>d.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q7d" -->You cannot =
specify=20
<CODE>FIRST.</CODE> with <CODE>LAST.</CODE><!-- =
InstanceEndEditable --></TD></TR></TBODY></TABLE>
<P></P>
<LI><!-- InstanceBeginEditable name=3D"q8text" -->What is the =
result of=20
submitting the following program? <PRE><FONT =
color=3D#003399>data work.addtoend;</FONT>
<FONT color=3D#003399>set clinic.stress2 end=3Dlast;</FONT>
<FONT color=3D#003399>if last;</FONT>
<FONT color=3D#003399>run;</FONT></PRE><!-- InstanceEndEditable -->
<P>
<TABLE border=3D0>
<TBODY>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Da name=3Dques8> </TD>
<TD> <EM>a.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q8a" -->an error<!-- =
InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Db name=3Dques8> </TD>
<TD> <EM>b.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q8b" -->an empty data =
set<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dc name=3Dques8> </TD>
<TD> <EM>c.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q8c" -->a continuous =
loop<!-- InstanceEndEditable --></TD></TR>
<TR vAlign=3Dtop>
<TD><INPUT type=3Dradio value=3Dd name=3Dques8> </TD>
<TD> <EM>d.</EM> </TD>
<TD><!-- InstanceBeginEditable name=3D"q8d" -->a data set =
that=20
contains one=20
observation<!-- InstanceEndEditable =
--></TD></TR></TBODY></TABLE>
<P></P>
<LI><!-- InstanceBeginEditable name=3D"q9text" -->At the start =
of DATA=20
step processing, during the compilation phase, variables are =
created in=20
the program data vector (PDV), and observations are set to:<!-- =
InstanceEndEditable -->=20
<P>
<TABLE border=3D0>
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