SAS认证考试(官方练习题集和校正答案)
1. A raw data file is listed below.1---+----10---+----20--+--son Frank 01/31/89 daughter June 12-2587 brother Samuel 01/17/51The following program is submitted using this file as input:data work. infile 'filespecification'; &insert INPUT statement here&Which INPUT statement correctly reads the values for the variable Birthdate as SAS date values? a. input relation b.$ first_name $ birthdate date9.; input relation $ first_name $ birthdate mmddyy8.; input relation $ first_name $ birthdate : date9.; input relation $ first_name $ birthdate : mmddyy8.;c.d.Correct answer:dAn informat is used to translate the calendar date to a SAS date value. The date values are in the form of two-digit values for month-day-year, so the MMDDYY8. informat must be used. When using an informat with list input, the colon-format modifier is required to correctly associate the informat with thevariable name. You can learn about? ?informats in Reading Date and Time Values the colon-format modifier in Reading Free-Format Data.2.A raw data file is listed below.1---+----10---+----20---+--Jose,47,210 Sue,,108The following SAS program is submitted using the raw data file above as input: &insert INFILE statement here& input name $The following output is desired:name age weight Jose Sue 47 . 210 108Which of the following INFILE statements completes the program and accesses the data correctly? a. infile 'file-specification' b. infile 'file-specification' c. infile 'file-specification' dlm=','; d. infile 'file-specification' Correct answer: bThe PAD option specifies that SAS pad variable length records with blanks. The MISSOVER option prevents SAS from reading past the end of the line when reading free formatted data. The DLM= option specifies the co however, consecutive delimiters are treated as one by default.The DSD option correctly reads the data with commas as delimiters and two consecutive commas indicating a missing value like those in this raw data file. You can learn about? ? ?the PAD option in Reading Raw Data in Fixed Fields the MISSOVER option in Creating Multiple Observations from a Single Record the DLM= option and the DSD option in Reading Free-Format Data.3.The following program is submitted: infile cards dlm=','; input agent1 $ agent2 $ agent3 $; jones,,brownjones,spencer, What is the value for the variable named Agent2in the secondobservation? a. Brown b. Spencer c. ' ' (missing character value) d. There is no value because only one observation is created. Correct answer: dThe CARDS statement enables you to read instream data. Any number of consecutive commas are considered to be a single delimiter as a result of the DLM= option, and the length of each variable defaults to 8 bytes. Therefore, the values jones, brownjon, and spencer are assigned to Agent1, Agent2, and Agent3, respectively, for the first observation. The rest of the data on the record is not read by the INPUT statement and is not output to the data set.You can learn about? ?the CARDS statement in Creating SAS Data Sets from Raw Data the default length of variables in Reading FreeFormat Data.4.A raw data file is listed below.1---+----10---+----20---+----30---+----40---+----50 TWOSTORY SANDERS ROAD $55,850 CONDO .5JEANS AVENUE $127,150The following program is submitted using this file as input:data work. infile 'file-specification'; &insert INPUT statement here&Which one of the following INPUT statements reads the raw data file correctly? a. input @1 style $8.+1 sqfeet 4. +1 bedrooms 1. @20 baths 3. street 16. @40 price dollar8; input @1 style $8 +1 sqfeet 4. +1 bedrooms 1. @20 baths 3. street $16 @40 price dollar8.; input @1 style $8. +1 sqfeet 4. +1 bedrooms 1. @20 baths 3. street $16. @40 price dollar8.; input @1 style $8. +1 sqfeet 4. +1 bedrooms 1. @20 baths 3 street 16. @40 price dollar8.;b.c.d.Correct answer:cFormatted input requires periods as part of the informat name. The period is missing from the variables Style and Street in Answer b, the variable Baths in Answer d, and the variable Price in Answer a (which is also missing a dollar sign to read the variable Street as a character value). You can learn about formatted input and informats in Reading Raw Data in Fixed Fields.5.The following SAS program is submitted at the start of a new SAS session:libname sasdata 'SAS-data-library'; data sasdata. set sasdata. profit=expenses- proc print data=The SAS data set Sasdata.Salesdata has ten observations. Which one of the following explains why a report fails to generate? a. The DATA step fails execution. b. The SAS data set Sales does not exist. c. The SAS data set Sales has no observations. d. The PRINT procedure contains a syntax error. Correct answer: bThe DATA step creates a permanent SAS data set, Sasdata.Salesdata. The PRINT procedure is printing a temporary SAS data set, Sales, that is stored in the Work library. At the beginning of the SAS session, Work.Sales does not exist. You can learn about?creating permanent data sets with the DATA step in Creating SAS Data Sets from Raw Data?temporary data sets inBasic Concepts.6.Which action assigns a reference named SALES to a permanent SAS data library? a. Issuing the command:libref SALES 'SAS-data-library'b. Issuing the command:libname SALES 'SAS-data-library'c. Submitting the statement:libref SALES 'SAS-data-library';d. Submitting the statement:libname SALES 'SAS-data-library';Correct answer:dThe LIBNAME statement assigns a reference known as a libref to a permanent SAS data library. The LIBNAME command opens the LIBNAME window. You can learn about the LIBNAME statement in Referencing Files and Setting Options.7.The following SAS program is submitted: &insert WHERE statement here&Which one of the following WHERE statements completes the program and selects only observations with a Hire_date of February 23, 2000? a. where hire_date='23feb2000'd; b. where hire_date='23feb2000'; c. where hire_date='02/23/2000'd; d. where hire_date='02/23/2000'; Correct answer: aA SAS date constant must take the form of one- or two-digit day, three-digit month, and two- or four-digit year, enclosed in quotation marks and followed by a d ('ddmmmyy&yy&'d). You can learn about SAS date constants in Data Sets from Raw Data. Creating SAS8.Which one of the following SAS date formats displays the SAS date value for January 16, 2002 in the form of 16/01/2002? a. DATE10. b. DDMMYY10. c. WEEKDATE10. d. DDMMYYYY10. Correct answer: bThe requested output is in day-month-year order and is 10 bytes long, so DDMMYY10. is the correct format. Although WEEKDATE10. is a valid SAS format, it does not display the SAS date value as shown in the question above. DDMMYYYY10. is not a valid SAS date format, and the DATEw. format cannot accept a length of 10. You can learn about? ?the DDMMYY10. format in Creating List Reports the WEEKDATE10. format in Reading Date and Time Values.9.Which one of the following displays the contents of an external file from within a SAS session? a. the LIST procedureb. the PRINT procedure c. the FSLIST procedure d. the VIEWTABLE window Correct answer: cThe PRINT procedure and VIEWTABLE window display the values in SAS data sets. The FSLIST procedure displays the values in external files. There is no LIST procedure in SAS. You can learn about? ?the PRINT procedure in Creating List Reports the VIEWTABLE window in Referencing Files and Setting Options.10.The SAS data set Sashelp.Prdsale contains the variables and Salary with 4 observations per Region. Sashelp.Prdsale is sorted primarily by Region and within Region by Salary in descending order.RegionThe following program is submitted: set sashelp. by regi if first. temp= if last. range=salary-For each region, what is the number of observation(s) written to the output data set? a. 0 b. 1 c. 2d. 4 Correct answer: cThe expression first.region is true once for each region group. The expression last.region is true once for each region group. Therefore, each OUTPUT statement executes once for a total of 2 observations in the output data set. You can learn about the FIRST.variable expression and the OUTPUT statement in Reading SAS Data Sets.11.The following SAS program is submitted:proc contents data=sasuser.The exhibit below contains partial output produced by the CONTENTS procedure.Data Set Name Member Type Engine Created Last Modified Protection Data Set Type Label Data Representation Encoding Residential housing for sale WINDOWS_32 wlatin1 Western (Windows) SASUSER.HOUSES Observations DATA V9 Tuesday, April 22, :25 PM Tuesday, April 22, :25 PM Variables Indexes Observation Length Deleted Observations Compressed Sorted 15 6 0 56 0 NO NOWhich of the following describes the Sasuser.Houses data set? a. The data set is sorted but not indexed. b. The data set is both sorted and indexed. c. The data set is not sorted but is indexed.d. The data set is neither sorted nor indexed. Correct answer: dThe exhibit above shows partial output from the CONTENTS procedure, In the top right-hand column of the output, you see that Indexes has a value of 0, which indicates that no indexes exist for this data set. Also, Sorted has a value of NO, which indicates that the data is not sorted. You can learn about the CONTENTS procedure in Referencing Files and Setting Options.12.The following SAS program is submitted:proc sort data=work. by fnaWhich one of the following represents how the observations are sorted? a. The data set Work.Test is stored in ascending order by both Fname and Salary values. b. The data set Work.Test is stored in descending order by both Fname and Salary values. c. The data set Work.Test is stored in descending order by Fname and ascending order by Salary values. d. The data set Work.Test is stored in ascending order by Fname and in descending order by Salary values. Correct answer: dThe DESCENDING keyword is placed before the variable name it modifies in the BY statement, so the correct description is in descending order by Salary value within ascending Fname values. You can learn about the SORT procedure and the DESCENDING keyword in Creating List Reports.13.The following SAS program is submitted: title='EDU'; if title='EDU' then Division='Education'; else if title='HR' then Division='Human Resources'; else Division='Unknown';Which one of the following represents the value of the variable Division in the output data set? a. Educatio b. Education c. Human Re d. Human Resources Correct answer: bThe length of the variable Division is set to 9 when the DATA step compiles. Since the value of the variable Title is EDU, the first IF therefore, the value of the variable Division is Education. You can learn about? ?the length of a variable in Understanding DATA Step Processing IF-THEN statements in Creating and Managing Variables.14.Which one of the following SAS programs creates a variable named City with a value of Chicago? a. data work.AirportCode='ord'; if AirportCode='ORD' City='Chicago'; data work. AirportCode='ORD';b.c.d.if AirportCode='ORD' City='Chicago'; data work. AirportCode='ORD'; if AirportCode='ORD' then City='Chicago'; data work. AirportCode='ORD'; if AirportCode='ORD'; then City='Chicago';Correct answer:cThe correct syntax for an IF-THEN statement is: IF expression THEN In this example, the variable City is assigned a value of Chicago only if the expression AirportCode='ORD' is true. You can learn about IF-THEN statements in Managing Variables. Creating and15.The following SAS program is submitted:data work. code='DAL523'; code='SANFRAN604'; code='HOUS731'; length code $ 20;Which one of the following is the length of the code variable? a. 6 b. 7 c. 10 d. 20 Correct answer: aThe DATA step first goes through a compilation phase, then an execution phase. The length of a variable is set during the compilation phase and is based on the first time the variable isencountered. In this case, the variable code is set to the length of the text string DAL523 which is 6 characters long. The next assignment statements are ignored during compilation. The LENGTH statement is also ignored since the length has already been established, but a note will be written to the log. You can learn about? ?the compilation phase of the DATA step in Understanding DATA Step Processing the LENGTH statement in Creating and Managing Variables.16.Which of the following statements creates a numeric variable named IDnumber with a value of 4198? a. IDnumber=4198; b. IDnumber='4198'; c. length IDnumber=8; d. length IDnumber $ 8; Correct answer: aThe first reference to the SAS variable in the DATA step sets the name, type, and length of the variable in the program data vector (PDV) and in the output SAS data set. The assignment statement IDnumber=4198; is the first reference and creates a numeric variable named IDnumber with a default storage length of 8 bytes. You can learn about? ?creating variables in the DATA step in Understanding DATA Step Processing numeric variables in Basic Concepts.17.The following program is submitted: input jobcode $ salary name $; FLAT1 70000 Bob FLAT2 60000 Joe FLAT3 30000 A if salary&60000 then description='Over 60'; else description='Under 60'; What is value of the variable named description when the value for salary is 30000?a. b. c. d.Under 6 Under 60 Over 60 ' ' (missing character value) Correct answer: aThe variable description is being created by the IFTHEN/ELSE statement during compilation. The first occurrence of the variable description is on the IF statement, and since it is assigned the value Over 60, the length of the variable is 7. Therefore, for the salary value of 30000, description has the value of Under 6 (the 0 is truncated.) You can learn about? ?the compilation phase of the DATA step in Understanding DATA Step Processing IF-THEN/ELSE statements in Creating and Managing Variables.18.A raw data file is listed below.1---+----10---+----20---+--10 2320 15The following program is submitted:data all_ infile 'file-specification'; &insert statement(s) here&Which statement(s) complete(s) the program and produce(s) a running total of the Receipts variable? a. total+ b. total 0; c. d. total=sum(total,receipts); Correct answer: a total=total+The SUM function and the assignment statement do not retain values across iterations of the DATA step. The sum statement total+ initializes total to 0, ignores missing values of receipt, retains the value of total from one iteration to the next, and adds the value of receipts to total. You can learn about the sum statement in Managing Variables. Creating and19.A raw data file is listed below.1---+----10---+----20---+--5 1 5 1 1941 1The following SAS program is submitted and references the raw data file above: infile 'file-specification';total=total+ What is the value of total whenthe data step finishesexecuting? a. 0 b. 1 c. 11 d. . (missing numeric value) Correct answer: dThe variable Total is assigned a missing value during the compilation phase of the DATA step. When the first record is read in, SAS processes: total=.+2; which results in a missing value. Therefore the variable Total remains missing for all observations. You can learn about? ?the compilation phase of the DATA step in Understanding DATA Step Processing using missing values with arithmetic operators in Creating SAS Data Sets from Raw Data.20.The following program is submitted: average=mean(6,4,.,2); What is the value of average?a. b. c. d.0 3 4 . (missing numeric value) Correct answer: cThe MEAN function adds all of the non-missing values anddivides by the number of non-missing values. In this case, 6 + 4 + 2 divided by 3 is 4. You can learn about the MEAN function in Data with SAS Functions. Transforming21.The following SAS program is submitted:data work.AreaC Phonenumber=; Code='('!!substr(Phonenumber,1,3)!!')';Which one of the following is the value of the variable Code in the output data set? a. ( 3) b. (312) c. 3 d. 312 Correct answer: aAn automatic data conversion is performed whenever a numeric variable is used where SAS expects a character value. The numeric variable is written with the BEST12. format and the resulting character value is right-aligned when the conversion occurs. In this example, the value of Phonenumber is converted to character and right-aligned before the SUBSTR function is performed. Since there are only 10 digits in the value of Phonenumber, the right-aligned value begins with two blanks. Therefore the SUBSTR function picks up two blanks and a 3, and uses the BEST12. format to assign that value to Code. Then, the parentheses are concatenated before and after the two blanks and a 3. You can learn about automatic data conversion and the SUBSTR function in Transforming Data with SAS Functions.22.The following SAS program is submitted:data work. products=7; do until (products gt 6); products+1;Which one of the following is the value of the variable products in the output data set? a. 5 b. 6 c. 7 d. 8 Correct answer: dA DO UNTIL loop always executes at least once because the condition is not evaluated until the bottom of the loop. In the SAS program above, the value of Products is incremented from 7 to 8 on the first iteration of the DO UNTIL loop, before the condition is checked. Therefore the value of Products is 8. You can learn about DO UNTIL loops in with DO Loops. Generating Data23.The following program is submitted:data work. set work.staff (keep=salary1 salary2 salary3); &insert ARRAY statement here&Which ARRAY statement completes the program and creates new variables? a. array salary{3}; b. array new_salary{3}; c. array salary{3} salary1-salary3; d. array new_salary{3} salary1-salary3; Correct answer: bAlthough each of the ARRAY statements listed above is a valid statement, only Answer B creates new variables named new_salary1, new_salary2 and new_salary3. Answer C and Answer D both create an array that groups the existing data set variables salary1, salary2, and salary3. Since the array in Answer A is named salary, it also uses the existing data set variables. You can learn about creating new variables in an ARRAY statement in Processing Variables with Arrays.24.Which of the following permanently associates a format with a variable? a. the FORMAT procedure b. a FORMAT statement in a DATA step c. an INPUT function with format modifiers d. an INPUT statement with formatted style input Correct answer: bTo permanently associate a format with a variable, you use the FORMAT statement in a DATA step. You can use the FORMAT procedure to create a user-defined format. You use the INPUT function to convert character data values to numeric values with an informat. You use the INPUT statement to read data into a data set with an informat. You can learn about? ? ? ? ?permanently assigning a format to a variable in Creating and Managing Variables the FORMAT statement in Creating List Reports the FORMAT procedure in Creating and Applying User-Defined Formats the INPUT function in Transforming Data with SAS Functions the INPUT statement in Reading Raw Data in FixedFields.25.The following report is generated:Style of homes CONDO RANCH SPLIT TWOSTORY Asking Price $99,313 $68,575 $77,983 $83,825n 4 4 3 4Which of the following steps created the report? a. proc freq data=sasuser.tables style price / format price dollar10.; label style=&Style of homes& price=&Asking price&; proc print data=sasuser. table style,n price*mean*f=dollar10.; label style=&Style of homes& price=&Asking price&; proc means data=sasuser. format price dollar10.; label style=&Style of homes& price=&Asking price&; proc report data=sasuser.
define style / group &Style of homes&; define price / mean format=dollar8. &Asking price&;b.c.d.Correct answer:dThe FREQ procedure cannot create the average asking price.The CLASS statement and the VAR statement are not valid for use with the PRINT procedure. The MEANS procedure output would have both the N statistic and the N Obs statistic since a CLASS statement is used. The REPORT procedure produced the report. You can learn about? ? ? ?the FREQ procedure in Producing Descriptive Statistics the PRINT procedure in Creating List Reports the MEANS procedure in Producing Descriptive Statistics the REPORT procedure in Creating Enhanced List and Summary Reports.26.A SAS report currently flows over two pages because it is too long to fit within the specified display dimension. Which one of the following actions would change the display dimension so that the report fits on one page? a. Increase the value of the LINENO option. b. Decrease the value of the PAGENO option. c. Decrease the value of the LINESIZE option. d. Increase the value of the PAGESIZE option. Correct answer: dThe PAGESIZE= SAS system option controls the number of lines that compose a page of SAS procedure output. By increasing the number of lines available per page, the report might fit on one page. You can learn about the PAGESIZE= option in Files and Setting Options. Referencing27.Which one of the following SAS REPORT procedure optionscontrols how column headings are displayed over multiple lines? a. SPACE= b. SPLIT= c. LABEL= d. BREAK= Correct answer: bThe SPLIT= option specifies how to split column headings. The SPACE=, LABEL= and BREAK= options are not valid options in PROC REPORT. You can learn about the SPLIT= option for the REPORT procedure in Creating Enhanced List and Summary Reports.28.The following SAS program is submitted:ods html file='newfile.html'; proc print data=sasuser. proc means data=sasuser. proc freq data=sasuser. proc print data=sasuser.How many HTML files are created? a. 1 b. 2 c. 3 d. 4 Correct answer: aBy default, one HTML file is created for each FILE= option or BODY= option in the ODS HTML statement. The ODS HTMLCLOSE statement closes the open HTML file and ends the output capture. The Newfile.html file contains the output from the PRINT, MEANS, and FREQ procedures. You can learn about the ODS HTML statement in Producing HTML Output.29.A frequency report of the variable Jobcode in the Work.Actors data set is listed below. Cumulative Cumulative Jobcode Frequency Percent Frequency Percent Actor I Actor II Actor III2 2 2 33.33 33.33 33.33 2 4 6 33.33 66.67 100.00Frequency Missing = 1The following SAS program is submitted:data work. set work. if jobcode in ('Actor I', 'Actor II') then joblevel='Beginner'; if jobcode='Actor III' then joblevel='Advanced'; else joblevel='Unknown';Which of the following represents the possible values for the variable joblevel in the Work.Joblevels data set? a. Advanced and Unknown only b. Beginner and Advanced only c. Beginner, Advanced, and Unknown d. ' ' (missing character value) Correct answer: aThe DATA step will continue to process those observations that satisfy the condition in the first IF statement AlthoughJoblevel might be set to Beginner for one or more observations, the condition on the second IF statement will evaluate as false, and the ELSE statement will execute and overwrite the value of Joblevel as Unknown.You can learn about? ?the IF statement in Creating SAS Data Sets from Raw Data the ELSE statement in Creating and Managing Variables.30.The descriptor and data portions of the Work.Salaries data set are shown below.Variable Type Len Pos name salary status Char 8 Char 8 Char 8 0 16 8name Lizstatus salary S 15,600 26,700 35,000Herman S Marty SThe following SAS program is submitted:proc print data=work. where salary&20000;What is displayed in the SAS log after the program is executed? a. A NOTE indicating that 1 observation is read. b. A NOTE indicating that 0 observations were read. c. A WARNING indicating that character values have been converted to numeric values. d. An ERROR indicating that the WHERE clause operator requires compatible variables.Correct answer:dSalary is defined as a character variable. Therefore, the value in the WHERE statement must be the character value 20,000 enclosed in quotation marks.You can learn about the WHERE statement in Reports.Creating List31.Which of the following statements is true when SAS encounters a syntax error in a DATA step? a. The SAS log contains an explanation of the error. b. The DATA step continues to execute and the resulting data set is complete. c. The DATA step stops executing at the point of the error and the resulting data set contains observations up to that point. d. A note appears in the SAS log indicating that the incorrect statement was saved to a SAS data set for further examination. Correct answer: aSAS scans the DATA step for syntax errors during the compilation phase. If there are syntax errors, those errors get written to the log. Most syntax errors prevent further processing of the DATA step. You can learn about how SAS handles syntax errors in the DATA step in Understanding DATA Step Processing.32.Which TITLE statement would display JANE'S DOG as the text of the title?a. b. c. d.title &JANE&S DOG&; title 'JANE&S DOG'; title &JANE'S DOG&; title 'JANE' ' 'S DOG';Correct answer:cThe title in a TITLE statement must be enclosed in a pair of matched quotation marks. Unbalanced quotation marks can cause problems for SAS. To hide an unmatched single quotation mark, surround the title text with matched double quotation marks. You can learn about? ?the TITLE statement in Creating List Reports unbalanced quotation marks in Editing and Debugging SAS Programs.33.The following SAS program is submitted: input animal1 $ animal2 $ mlgrams1 mlgrams2; hummingbird ostrich 00000.87 ;Which one of the following represents the values of each variable in the output data set? a. animal1 animal2 mlgrams1 mlgrams2hummingb ostrich 00000b. animal1animal2 mlgrams1mlgrams2hummingb ostrich00000.87c. animal1animal2 mlgrams1 mlgrams2 00000hummingbird ostrichd. animal1animal2 mlgrams1mlgrams2hummingbird ostrich00000.87Correct answer:bThe CARDS statement is an alias for the DATALINES statement. In the INPUT statement, you must specify a dollar sign ($) after the variable name in order to define a character variable. If you do not specify otherwise, the default storage length for a variable is 8. In the example above, the character value hummingbird is truncated to hummingb. You can learn about? ? ?the DATALINES statement in Creating SAS Data Sets from Raw Data the INPUT statement in Reading Free-Format Data the default storage length for variables in Basic Concepts.34.The SAS data sets Work.Employee and Work.Salary are shown below. Work.Employeefname age Bruce Dan 30 40Work.Salaryfname salary Bruce Bruce Dan
25000The following merged SAS data set is generated:Work.Empdatafname age totsal Bruce Dan 30 40 Which one of the following SAS programs created the merged data set? a. data work.merge work.employee work. if first.fname then totsal=0; totsal+ if last. data work.empdata(drop=salary); merge work.employee work. if first.fname then totsal=0; totsal+ if last. data work. merge work.employee work.salary(drop=salary); if first.fname then total=0; totsal+ if last. data work. merge work.employee work. if first.fname then total+b.c.d.Correct answer:bThe MERGE and BY statements allow you to match-merge two or more SAS data sets. The BY statement creates two temporary variables, First.Fname and Last.Fname for BY group processing. The SUM statement is used to add salary for each BY group. The variable on the left side of the plus sign is the variable that is retained and has an initial value of 0. The expression on the right side of the plus sign is added to thevariable on the left side of the plus sign to create a grand total. The accumulating variable, totsal, is reset back to 0 when you encounter a new BY group value (First.Fname is true). To output just the totals for each BY group, use the explicit OUTPUT statement when you reach the last occurrence of each Fname value. You can learn about the MERGE statement, the BY statement and match-merging in Combining SAS Data Sets.35.The contents of the SAS data set Sasdata.Group are listed below.name age Janice Henri Michele Susan 10 11 11 12The following SAS program is submitted using the Sasdata.Group data set as input:libname sasdata 'SAS-data-library'; set sasdata. file 'file-specification'; put name $15. @5 age 2.;Which one of the following describes the output created? a. a raw data file only b. a SAS data set named Group only c. both a SAS data set named Group and a raw data file d. The program fails execution due to errors. Correct answer: cThe DATA step creates a temporary data set named Group and reads data from the permanent SAS data set named Sasdata.Group into it. The FILE statement creates a raw datafile by writing out values for the variables Name and Age to the file that is specified within the quotation marks. You can learn about? ?temporary data sets in the FILE statement in Raw Data.Basic Concepts Creating SAS Data Sets from36.The SAS data set Employee_info is listed below.employee bonus 98
133.15 234.34 111.12The following SAS program is submitted:proc sort data=employee_ &insert BY statement here&Which one of the following BY statements completes the program and sorts the data in sequential order by descending bonus values within ascending employee values? a. by desce b. by emplo c. by emplo d. by desce Correct answer: cYou use the keyword DESCENDING in a BY statement to specify that data will be sorted by values in descending order. The DESCENDING keyword applies to the variable that is listed immediately after it. To sort on values of bonus within sorted values of employee, you list employee first in the BYstatement. You can learn about the DESCENDING keyword and the BY statement in Creating List Reports.37.The following SAS program is submitted:data work. length jobcode $ 12; set work.The Work.Department SAS data set contains a character variable named jobcode with a length of 5. Which of the following is the length of the variable jobcode in the output data set? a. 5 b. 8 c. 12 d. The value cannot be determined because the program fails to execute due to syntax errors. Correct answer: cThe LENGTH statement enables you to specify the length of a character variable. Since the LENGTH statement appears before the SET statement, SAS will set the length of jobcode to 12. You can learn about the LENGTH statement in and Managing Variables. Creating38.Assume the SAS data set Sasuser.Houses has four numeric variables. The following SAS program is submitted:proc means data=sasuser. &insert statement(s) here&The following report is produced: styleCONDO RANCH SPLIT TWOSTORYN Obs VariableMean4 bedrooms 2.7500000 baths 2. bedrooms 2.2500000 baths 2. bedrooms 2.6666667 baths 1. bedrooms 3.0000000 baths 1.8750000Which of the following statement(s) create(s) this report? a. b. c. d. Correct answer:cThe CLASS statement specifies the category variable(s) for group processing. The VAR statement specifies the numeric variable(s) for which to calculate statistics. You can learn about the CLASS statement and the VAR statement in Producing Descriptive Statistics.39.An HTML file contains a SAS report. Which ODS statement option is used to specify the name of the HTML file? a. OUT= b. FILE= c. HTML= d. HTMLFILE= Correct answer: bThe FILE= option identifies the file that contains the HTML output. The FILE= option is an alias for the BODY= option in the ODS HTML statement. You can learn about the FILE= option in the ODS HTML statement in Producing HTML Output.40.The following SAS program is submitted:data work. set sasuser. array t{3} &insert text here& (5, 10, 15);Which one of the following completes the ARRAY statement and creates data elements that are not included in the SAS data set Work.Test? a. _DROP_ b. _TEMP_ c. _TEMPORARY_ d. No extra text is needed. Correct answer: c_TEMPORARY_ is a keyword used in the ARRAY statement to create temporary data elements. By default, the ARRAY statement creates new data set variables or references existing variables for use by the array. You can learn about the _TEMPORARY_ keyword and the ARRAY statement in Processing Variables with Arrays.41.A raw data file is listed below.1---+----10---+----20---+--01/05/1989 Frank 11 12/25/1987 June 13 01/05/1991 Sally 9The following SAS program is submitted using the raw data file as input:data work. infile 'file-specification'; input @1 date_of_birth mmddyy10. @15 first_name $5. @25 age 3; proc print data=work.Which one of the following is the result? a. The program executes, but the age values are missing in the output. b. The program executes, but the date values are missing in the output. c. The program fails to execute because the age informat is coded incorrectly. d. The program fails to execute because the date informat is coded incorrectly. Correct answer: aValues for the variable age are missing in the output because the informat for age is coded incorrectly. Since age is standard numeric input, it should use the w.d informat to specify a field width of 3 in the INPUT statement. You can learn about the w.d informat in in Fixed Fields. Reading Raw Data42.Assume that SAS data sets Sasdata.Products and Sasdata.Sales both contain the Prod_ID variable. Which of the following SAS DATA steps returns only exceptions or non matches? a. libname sasdata 'SAS-data-library'; merge sasdata.products sasdata. by prod_ if ins=1 or inp=1;b.c.d. libname sasdata 'SAS-data-library'; merge sasdata.products(in=inp) sasdata.sales(in=ins); by prod_ if ins=1 and inp=1; libname sasdata 'SAS-data-library'; merge sasdata.products(in=inp) sasdata.sales(in=ins); by prod_ if ins=0 and inp=0; libname sasdata 'SAS-data-library'; merge sasdata.products(in=inp) sasdata.sales(in=ins); by prod_ if ins=0 or inp=0;Correct answer:dBy default, DATA step match-merges combine all observations in all input data sets. To include only unmatched observations from your output data set, you can use the IN= data set option to create and name a temporary variable that indicates whether the data set contributed to the current observations. If the value of the IN= variable is 0, the data set did not contribute to the if the value is 1, the data set did contribute to the current observation. You can use a subsetting IF statement to only include those observations that have a value of 0 for the IN= variable of either the Sasdata.Products data set or the Sasdata.Sales data set. Since an unmatched observation might come from either input data set, you do not need to specify that the IN= variables for both Sasdata.Products and Sasdata.Sales have values of 0. You can learn about the IN= data set option in SAS Data Sets. Combining43.The following SAS program is submitted:libname sasdata 'SAS-data-library'; libname labdata 'SAS-data-library'; data labdata.boston labdata.dallas(drop=city dest equipment); set sasdata.cities(keep=orig dest city price equipment); if dest='BOS' then output labdata. else if dest='DFW' then output labdata.Which variables are output to both data sets? a. price and orig only b. city and equipment only c. city, price, and equipment only d. city, price, orig, and equipment Correct answer: aIn the program above, the KEEP= option specifies that 5 variables (orig, dest, city, price, and equipment) are read from the input data set. All of these variables are output to Labdata.Boston. In the Labdata.Dallas output data set, the DROP= option specifies that city, dest, and equipment are excluded from the data set so that only orig and price are included. You can learn about the KEEP= option in Managing Variables. Creating and44.The following SAS program is submitted:proc contents data=sasuser._all_Which one of the following is produced as output? a. the list of all data set names in the Sasuser library only b. the descriptor portion of the data set named Sasuser._All_ c. the descriptor portion of every data set in the Sasuser library only d. the list of data set named in the Sasuser library plus the descriptor portion of every data set in the Sasuserlibrary. Correct answer: aYou can use the CONTENTS procedure to create SAS output that describes the contents of a library. _ALL_ requests a listing of all files in the library, and NODS suppresses the printing of detailed information about each file in the output. You can learn about the CONTENTS procedure in Referencing Files and Setting Options.45.The following SAS program is submitted:data work. length city $20; city='Paris'; city2=trim(city);Which one of the following is the length of the city2 variable? a. 5 b. 6 c. 8 d. 20 Correct answer: dThe LENGTH statement specifies that the variable city has a length of 20 characters. The TRIM function in the assignment statement for city2 removes trailing blanks from the value. However, the length of the city2 variable is set to 20 because city has a length of 20, and SAS pads the trimmed value with extra blanks. You can learn about? ?the LENGTH statement in Reading Free-Format Data the TRIM function in Transforming Data with SASFunctions.46.A raw data record is listed below.1---+----10---+----20---+--$23,456 750The following SAS program is submitted: infile 'file-specification'; input salary $ 1-7 raise 9-11; &insert statement here&Which one of the following statements completes the program and adds the values of salary and raise to calculate the expected values of the newsalary variable? a. newsalary=salary + b. newsalary=put(salary,comma7.) + c. newsalary=input(salary,comma7.) + d. newsalary=put(salary,comma7.) + put(raise,3.); Correct answer: cYou must convert the value of salary from character to numeric in order to perform an arithmetic function on it. You use the INPUT function to convert a character value to a numeric value. You can learn about the INPUT function in Data with SAS Functions. Transforming47.The following SAS program is submitted:data work. do i=1 to 6 by 2; trip +Which one of the following is the value of the variable trip in the output data set? a. 2 b. 3 c. 9 d. 10 Correct answer: cThe sum variable in a sum statement is automatically set to 0 before the first observation is read from the data set. The sum variable in the statement above is increased by the value of i on each iteration of the DO the value of i is set to 1 on the first iteration of the DO loop and increases by 2 on each additional iteration until it is greater than 6. Therefore, the value of Trip is equal to 0 + 1 + 3 + 5, which is 9. You can learn about? ?the sum statement in Creating and Managing Variables DO loops in Generating Data with DO Loops.48.The following SAS program is submitted:proc report data= column age choice1; &insert DEFINE statement here& define choice1/Which one of the following DEFINE statements completes the program and displays values of the variable Age in ascending order? a. define age/ b. define age/ c. define age/ d. define age/ Correct answer: bYou use a DEFINE statement to describe how to order and use variables in your report. To specify Age as an order variable, you use the ORDER usage option in the DEFINE statement. An order variable orders the detail rows in a report according to their formatted values. By default, the order is ascending. You can learn about the DEFINE statement and order variables in Creating Enhanced List and Summary Reports.49.Which one of the following statements is true when SAS encounters a data error? a. The execution phase is stopped, and a system abend occurs. b. A missing value is assigned to the appropriate variable, and execution continues. c. The execution phase is stopped, and a SAS data set is created with zero observations. d. A missing value is assigned to the appropriate variable, and execution stops at that point. Correct answer: bUnlike syntax errors, invalid data errors do not cause SAS to stop processing a program. SAS handles invalid data errors by assigning a missing value to the appropriate variable and writing a message to the SAS log. You can learn about how SAS handles invalid data errors in Creating SAS Data Sets from Raw Data.50.The following SAS program is submitted: input country $8. date mmddyy10.;Germany 12/31/2000 France 01/32/2001 ;Which one of the following is the value of the variable _ERROR_ when the variable _N_ has a value of 2? a. 0 b. 1 c. true d. false Correct answer: b_N_ and _ERROR_ are automatic variables that can be used for DATA step processing but that are not written to the output data set. _N_ counts the number of times that the DATA step begins to execute, and _ERROR_ signals the occurrence of an error that is caused by the data during execution. A value of 0 indicates no error while a value of 1 indicates one or more errors. In the program above, the value for date in the second observation is invalid. You can learn about the automatic variables _N_ and _ERROR_ in Understanding DATA Step Processing.
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