MATH 707-ST: Introduction to Statistical Computing with SAS and R. MID-TERM EXAM (Writing part) Fall, (Time allowed: TWO Hours)

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1 MATH 707-ST: Introduction to Statistical Computing with SAS and R MID-TERM EXAM (Writing part) Fall, 2013 (Time allowed: TWO Hours) Highlight your answer clearly for each question. There is only one correct answer for each question. 1. Given the SAS data set EMPLOYEES: NAME SALARY Innis Jolli Ellis Liu The following SAS program is submitted: proc print data = employees; where name like '_i%'; What is contained in the output? a. Innis, Ellis, and Liu only b. Liu only c. Innis, Jolli, Ellis, and Liu d. Innis and Ellis only 2. A raw data file is listed below /05/1989 Frank 11 12/25/1987 June 13 01/05/1991 Sally 9 The following SAS program is submitted using this file as input: data work.family; infile 'file-specification'; date_of_birth first_name age 3; proc print data=work.family noobs; The following output is generated for the Work.Family data set: 1

2 Date_of_birth First_name Age Frank June Sally. Which of the following statements is true regarding the Work.Family output? a. The output has the expected data values. b. The output does not have the expected data values due to an invalid data set name. c. The output does not have the expected data values due to an invalid informat for Age only. d. The output does not have the expected data values due to invalid informats for both Age and Date_of_birth. 3. The following SAS program is submitted: data employees; infile 'file-specification'; name date department $; How many numeric variables are created? a. 0 b. 1 c. 2 d A raw data file is listed below Jose,47,210 Sue,,108 The following SAS program is submitted using this file as input: data employeestats; <insert INFILE statement here>; input name $ age weight; The following output is desired: name age weight Jose Sue. 108 Which of the following INFILE statements completes the program and accesses the data correctly? a. infile 'file-specification' pad; b. infile 'file-specification' dsd; c. infile 'file-specification' missover; 2

3 d. infile 'file-specification' dlm=','; 5. When the following SAS program is submitted, the data set SASDATA.PRDSALES contains 2000 observations: libname sasdata 'SAS-data-library'; options obs = 500; proc print data = sasdata.prdsales (firstobs = 100); options obs = max; proc means data = sasdata.prdsales (firstobs = 300); How many observations are processed by each procedure? a. 400 for PROC PRINT, 1700 for PROC MEANS b. 401 for PROC PRINT, 1701 for PROC MEANS c. 401 for PROC PRINT, 1700 for PROC MEANS d. 500 for PROC PRINT, 2000 for PROC MEANS 6. A raw data file is listed below TWOSTORY SANDERS ROAD $55,850 CONDO JEANS AVENUE $127,150 The following program is submitted using this file as input: data work.houses; infile 'file-specification'; <insert INPUT statement here> Which one of the following INPUT statements reads the raw data file correctly? a. style $8. +1 sqfeet bedrooms baths 3. street price dollar8.; b. style $8 +1 sqfeet bedrooms baths 3. street price dollar8.; c. style $8. +1 sqfeet bedrooms baths 3. street price dollar8.; d. style $8. +1 sqfeet bedrooms baths 3 street price dollar8.; 7. The following SAS program is submitted at the start of a new SAS session: libname sasdata2008 'SAS-data-library'; data sasdata.sales; set sasdata2008.salesdata; profit=expenses-revenues; proc print data=sasdata.sales; The SAS data set Salesdata has 10 observations. Which one of the following answers explains why a report fails to generate? a. The DATA step fails to execute. 3

4 b. The SAS data set Sales has 10 observations. c. The SAS data set Sales does not exist in the work library. d. The PRINT procedure statement syntax is incorrect. 8. The following SAS program is submitted: data work.clients; calls=6; do until(calls gt 9); calls+1; end; calls+1; What is the result? a. The variable Calls has a value of 9 in the output data set. b. The variable Calls has a value of 10 in the output data set. c. The variable Calls has a value of 11 in the output data set. d. The variable Calls has no value. The program fails to execute. 9. The following SAS program is submitted: proc sort data=payroll; by EmployeeIDNumber; How are the observations sorted? a. Payroll is re-created in sorted order by EmployeeIDNumber. b. Payroll is stored in original order, and a new data set Payroll is created in sorted order by EmployeeIDNumber. c. Payroll is stored in original order, and a new data set Payrollsorted is created in sorted order by EmployeeIDNumber. d. Payroll is re-created in sorted order by EmployeeIDNumber, and a new data set Payroll is created in sorted order by EmployeeIDNumber. 10. Which one of the following SAS programs creates a variable named City with a value of Chicago? a. data work.airports; AirportCode='ord'; if AirportCode='ORD' City='Chicago'; b. data work.airports; AirportCode='ORD'; if AirportCode='ORD' City='Chicago'; c. data work.airports; AirportCode='ORD'; if AirportCode='ORD' then City='Chicago'; d. data work.airports; AirportCode='ORD'; 4

5 if AirportCode='ORD'; then City='Chicago'; 11. The SAS data set Employees is listed below. Employees Name Salary Patel Payne Ellis Liu The following SAS program is submitted: proc print data=employees; where name? 'e' and name contains E ; What is the result? a. No observations are written to the report. b. The observation for Ellis only is written to the report. c. The observations for Patel and Payne only are written to the report. d. The observations for Patel, Payne, and Ellis only are written to the report. 12. The following SAS program is submitted: proc sort data=houses; by style; proc print data=houses; <insert SAS statement(s) here> The following list report is generated: style bedrooms baths price CONDO $80, $79, $127, $110,700 TWOSTORY $107,250 5

6 2 1.0 $55, $569, $102,950 Which of the following SAS statements completes the program and creates the desired report? a. id style; var bedroom baths price; b. id style; var style bedrooms baths price; c. id style; by style; var bedrooms baths price; d. id style; by style; var style bedrooms baths price; 13. The following SAS program is submitted: options pageno=3 number; proc print data=sasuser.houses; proc means data=sasuser.shoes; The report created by the PRINT procedure generates five pages of output. What is the page number on the first page that is generated by the MEANS procedure? a. 3 b. 4 c. 7 d The descriptor and data portions of the Work.Salaries data set are shown below. Variable Type Len Pos name Char 8 0 salary Char 8 16 status Char 8 8 name status salary Liz S 15,600 Herman S 26,700 Marty S 35,000 The following SAS program is submitted: proc print data=work.salaries; where salary<20000; No observations are output. Which of the following answers would result in a report of individuals with Salary less than $20,000 upon re-execution of the program? a. Right justify the Salary value in the WHERE statement in the PRINT step. b. Use a PUT function to write the Salary values with leading zeroes in a DATA step before the PRINT step. 6

7 c. Change (which is a numeric constant) to '20,000' (which is a character constant) in the WHERE statement in the PRINT step. d. Change the < operator to the le operator in the WHERE statement in the PRINT step. 15. name siblings bdate allowance hobby1 hobby2 hobby3 $10.; What is the length of bdate and hobby1? a. bdate = 8 and hobby1 = 8 b. bdate = 8 and hobby1 = 10 c. bdate = 10 and hobby1 = 8 d. bdate = 10 and hobby1 = The following SAS program is submitted: data work.flights; destination = 'CPH'; select(destination); when('lhr') CITY = 'London'; when('fra') CITY = 'Frankfurt'; otherwise; end; What are the length and value of the CITY variable? a. length is 6, value is CPH b. length is 9, value is London c. length of 6, value is (missing character value) d. length of 9, value is Frankfurt 17. Given the following DATA step: data loop; x = 0; do index = 1 to 5 by 2; x = index ; end; Upon completion of execution, what are the values of the variables X and INDEX in the SAS data set named LOOP? a. x = 3, index = 3 b. x = 3, index = 4 c. x = 5, index = 5 d. x = 5, index = 6 e. x = 5, index = 7 7

8 18. The following SAS SORT procedure step generates an output data set: proc sort data = sasuser.houses out = report; by style; In which library is the output data set stored? a. WORK b. REPORT c. HOUSES d. SASUSER 19. SAS treats Date as a numeric value. The initial date that is recorded as the value 0 is (a) 01/01/1980 (b) 01//01/1970 (c) 01/01/1960 (d) 01/01/ Which of the following is a correct format for a specific date on 12/31/2000 for the following IF statement IF hireddate = then bonus = salary *.15; (a) 12/31/2000 (b) 31DEC2000 d (c) DEC (d) 12/31/2000 d (e) DEC d 21. Which of the following format reads the Date 12NOV2004: (a) Date9. (b) DDMMYY9. (c) DDMMMYYYY9. (d) None of the above 22. In a SAS program, when INFILE statement is used, the DATA step usually reads (a) procedure for analyze data (b) external data file (c) SAS data file (d) none of these 23. How many observations are in the output from the following program, assuming the SAS data set old has more than 20 observations: Options firstobs=6 obs = 20; Data new1; set old; Run; PROC PRINT data = work.new1; RUN; (a) None (b) 5 (c) 10 (d) 15 (e) 25 8

9 24. How many observations are in the output from the following program, assuming the SAS data set old has more than 20 observations: Options firstobs=6 obs = 20; Data new1; set old; If _N_ > 10; RUN; PROC PRINT data = work.new1 (firstobs = 1); RUN; (a) None (b) 5 (c) 10 (d) 15 (e) What happens if you submit the following program? PROC SORT data = clinic.diabetes ; PROC PRINT data = clinic.diabetes; Var age height weight pulse; Where sex = F ; RUN; (a) The PROC SORT step runs successfully, but the PROC PRINT step generates errors and stop processing. (b) The PROC PRINT step runs successfully, printing observations in their sorted order. (c) The PROC SORT step permanently sorts the input data set. (d) The RPCO SORT step generates errors and stops processing, but the PROC PRINT step runs successfully,- printing observations in their original (unsorted) order. 26. Which of the following programs correctly read the Excel file, salary.xlsx stored in the folder Ex_data in D-drive: (a) Libname Excell_data D:\Ex_data\salary.xlsx ; Data salary; Set Excell_data. salary$ n ; RUN; (b) Libname Ex_data D:/Ex_data/salary.xlsx ; Data salary; Set Ex_data.salary; RUN; (c) Libname Ex_data D:\Ex_data\salary.xlsx ; Data salary; Set Ex_data.salary.xlsx; RUN; (d) Libname Ex_data D:\Ex_data\salary.xlsx ; Data salary; Set Ex_data. salary$ n ; RUN; 9

10 27. Suppose you run a program that causes three DATA step errors. What is the value of the variable _ERROR_ when the observation that contains the third error is processed? (a) 0 (b) 1 (c) 2 (d) The following observation is stored in a SAS data set named EMPLOYEES: LNAME FNAME JOBCODE Whitley Sam NA1 If the DATA step below is executed, what will be the value of the variable JOBDESC in the output SAS data set when this observation is processed: data navigate; set employees; if jobcode = 'NA1' then jobdesc = 'Navigator'; a. navigator b. Navigator c. NAVIGATOR d. a missing value 29. The below three program blocks are submitted A) Data target_data ; Set base_data (keep = var1 var2 var3 ); Run; B) Data target_data ; Set base_data; keep = var1 var2 var3 ; Run; C) Data target_data (keep = var1 var2 var3 ); Set base_data; Run; If the user needs only var1, var2 and var3 to work with, which step is most efficient? a. A b. B c. C d. A&B e. None 30. The following SAS program is submitted: 10

11 data test(drop=age); set sashelp.class(keep=name age gender height weight); drop=gender; newage=age+1; Sashelp.Class contains 5 variables. What is the result? a. No variables are written to the data set Work.Test. b. 4 variables are written to the data set Work.Test. c. 5 variables are written to the data set Work.Test. d. 6 variables are written to the data set Work.Test. 31. The following SAS program is submitted: data _null_; set old(keep=sales1 sales2); file 'file-specification'; put sales1 sales2; What is the result? a. A raw data file is created with no delimiter separating the fields. b. A raw data file is created with a space delimiter separating the fields. c. A raw data file is created with a comma delimiter separating the fields. d. No raw data file is created. The DATA step fails execution because no delimiter is specified. 32. The following statements are submitted Data Test; today = '20dec2005'd; format today mmddyy10.; Which of the following statement is true? a. Today variable displays like 12/20/2005 b. Data step not executed due to wrong format mmddyy. c. Today is displayed as 20DEC What is the result from running the following program in the data set score: 11

12 Data rawscore; Input name $ Quiz1 Datalines; Tom Jerry Mike Julie Jean ; Run; Data score; Set rawscore point = 3; Output; stop; a. None, since there is a syntax error in the SET statement. b. None since the rawscore data set only consists of one observation. c. It has one observation, which is Mike d. It has one observation, which is Tom What is the result from running the following program in the data set score: Data rawscore; Input name $ Quiz1 Datalines; Tom Jerry Mike Julie Jean ; Run; Data score; num=3; Set rawscore point = num; stop; a. None, since there is a syntax error in the SET statement. b. None since the SAS program can not reach the end of file. 12

13 c. None since the SAS program can not reach the end of the Data Step is make the implicit output. d. It has one observation, which is Mike e. It has one observation, which is Tom Answer Q35 to Q38 based on the following submitted program: Input name $ gender $ Quiz1 Datalines; Tom M Jerry M Mike M Julie F Jean F ; Run; proc print; Proc sort; by gender; Data score (keep= gender Avg_q1 Avg_q2); Set rawscore (drop = name); BY gender; Ncase+1; Sumq1+quiz1; Sumq2+quiz2; If last.gender then do; Avg_q1=sumq1/ncase; Avg_q2=sumq2/ncase; ncase = 0; sumq1=0; sumq2=0; End; output; proc print; 35. How many variables are created in the Program data Vector in the Data Step: Data Score prior to output to the Score data set: a. 3 b. 4 c. 5 d. 9 e How many variables are outputs to the SAS data Score: a. 3 b. 4 c. 5 d. 9 e

14 37. What is the Avg_q1 for Gender = F after running the program? a. 20 b c d e. Cannot be computed due to syntax error 38. If we delete the statement OUTPUT; from the program, what is the effect on the data set Score? a. There is no effect. b. The number of observations is decreased from 5 to 2 c. The number of observations is increased from 2 to 5 d. The program will have syntax error. 39. In a SAS program, the PROC step usually reads (a) procedure for analyze data (b) external data file (c) SAS data file (d) none of these 40. Which of the following statements selects from a data set only those observations for which the value of the variable Style is RANCH, SPLIT, or TWOSTORY? (a) WHERE STYLE = RANCH OR SPLIT OR TWOSTORY ; (b) WHERE STYLE IN RANCH OR SPLIT OR TWOSTORY ; (c) WHERE STYLE IN ( RANCH, SPLIT, TWOSTORY ) ; (d) WHERE STYLE IN (RANCH, SPLIT, TWOSTORY ) ; 14