Choose.. X Home Exams Certifications
 

SAS Interview Questions

1 . Mention what is the difference between nodupkey and nodup options?

  • The identical observations are checked and removed through NODUP option. NODUPKEY option checks for all BY variable values and if found, it will eliminate that.

2 . Explain BOR function?

  • It is a bitwise logical operation and is used to return bitwise logical OR between two statements.

3 . Explain what does PROC print, and PROC contents are used for?

  • PROC print outputs a listing of the values of some or all of the variables in a SAS data set. PROC contents tells the structure of the data set rather than the data values.

4 . What is the use of $BASE64X?

  • By using base 64 encoding, character data is converted into ASCII text.

5 . What will CALENDAR procedure do?

  • CALENDAR procedure will show data in a monthly calendar format from SAS data set

6 . What is Debugging?

  • Debugging is the technique for testing the program logic and this can be done with the help of debugger.

7 . Explain ANYDIGIT function?

  • It is used for searching a character string and as soon as string is found it will return it.

8 . Explain BY-Group processing?

  • BY statement is used by BY-Group processing so that it can process data which are indexed, grouped or ordered based on the variables.

9 . Explain what Procglm does?

  • The functions of Procglm are covariance analysis, variance analysis, multivariate and repeated analysis of variance.

10 . Explain BMDP procedure?

  • For analyzing data BMPD procedure is used.

11 . Explain PROC UNIVARIATE?

  • PROC UNIVARIATE is used for elementary numeric analysis and will examine how data is distributed.

12 . Explain TRANSLATE function?

  • TRANSLATE Function : Characters which are specified in a string are replaced by the characters specified by us.

13 . What does CDISC stands for?

  • CDISC stands for Clinical Data Interchange Standards Consortium.

14 . Explain FILECLOSE data set option?

  • When data set is closed, its tape positioning is defined by FILECLOSE.

15 . What do you mean by ALTER data set option?

  • It is used for assigning an ALTER password which will stop the users from changing  the file.

16 . Define MAX() function?

  • Max() function is used to return the largest value.

17 . How do I Create a SAS Data Set with Compressed Observations?

  • To create a compressed SAS data set, use the COMPRESS=YES option as an output DATA set option or in an OPTIONS statement.Compressing a data set reduces its size by reducing repeated consecutive characters or numbers to 2-bye or 3-byte representations.To uncompress observations, you must use a DATA step to copy the data set and use option COMPRESS=NO for the new data set.
    The advantages of using a SAS compressed data set are reduced storage requirements for the data set and fewer input/output operations necessary to read from and write to the data set during processing. The disadvantages include not being able to use SAS observation number to access an observation. The CPU time required to prepare compressed observations for input/output observations is increased because of the overhead of compressing and expanding the observations. (Note: If there are few repeated characters, a data set can occupy more space in compressed form than in uncompressed form, due to the higher overhead per observation.) For more details on SAS compression see “SAS Language: Reference, Version 6, First Edition, Cary, NC: SAS Institute Inc., 1990”.

18 . Explain what is the use of function Proc summary?

  • Proc Summary is same as Proc Means i.e. it will give descriptive statistics but it will not give output as default, we have to give an option print then only it will give the output.

19 . Explain what is PDV?

  • Program Data Vector is the area of memory where data sets are created through SAS system i.e. one at a time. When program is executed an input buffer is created which will read the data values and make them assign to their respective variables.

20 . What’s the difference between VAR B1 – B3 and VAR B1 -- B3?

  • Single Dash specifies consecutively numbered variables. Double Dash specifies variables available within that data set. For example:
  • Data Set: ID NAME B1 B2 C1 B3Then, B1 – B3 would return B1 B2 B3
    And B1 – B3 would return B1 B2 C1 B3.

21 . What are the functions which are used for Character handling functions?

  • UPCASE and LOWCASE are the functions which are used for character handling functions.

22 . Describe any one SAS function?

  • RIM : removes trailing blanks from a character expression
  • Str1 = ‘my’;
    Str2 = ‘dog’;
    Result = TRIM (Str1)(Str2);
    Result = ‘mydog’

23 . Explain what is SAS? What are the functions does it performs?

  • SAS i.e. Statistical Analysis System is a combined set of software solutions which helps user to analyze data.
    • It can change, manipulate, analyze & retrieve data.
    • Numerical analysis can be done.
    • Report writings.
    • Quality can be improved.

24 . Explain SUBSTR function?

  • SUBSTR Function is used for extracting a string or replacing contents of character value.

25 . How can SAS program be validated?

  • By writing OPTIONS OBS=0 at the starting of the code and if execution of code is On PC SAS than log will be detected itself by highlighted colors. These are the two ways for validating an SAS program

26 . What is the use of DIVIDE function?

  • DIVIDE function is used to return the division result.

27 . What does ODS stands for?

  • ODS stands for output delivery system.

28 . What is the basic syntax style in SAS?

  • The points important for running SAS program are :
    1. DATA statement, which names your data set.
    2. The names of the variables in your data set are described by INPUT statement.
    3. Statement should be ended through semi-colon(;).
    4. Space between word and statement should be there.

29 . Compare SAP BO & SAS BI

  • CriteriaSAP BOSAS BI
    Deploying data forHigh level of visualization, customer-friendlyQuick data integration with diverse sources
    PresentationVery GoodAverage
    Ad hoc analysisVery GoodAverage
    Mobile BIGoodVery Good
    AnalyticsPredictive analyticsEasy analytics
    ApplicationFront-end suite to sort, view and analyze BI dataCombining BI & Analytics for enterprise-grade data

30 . What do you mean by CALL PRXFREE Routine?

  • CALL PRXFREE routine is used for Character String Matching and is used for allocation of free memory for perl regular expression.

31 . Compare SAS STATA & SPSS?

  • Each package offers its own unique strengths and weaknesses. As a whole, SAS, Stata and SPSS form a set of tools that can be used for a wide variety of statistical analysis. With Stat/Transfer it is very easy to convert data files from one package toanother in just a matter of seconds or minutes.
    Therefore, there can be quite an advantage to switching from one analysis package to another depending on the nature of your problem.
    For example, if you were performing analysis using mixed models you mightchoose SAS, but if you were doing logistic regression you might choose Stata, and if you were doing analysis of variance you might choose SPSS. If you are frequently performing statistical analysis, we would strongly urge you to consider making each oneof these packages part of your toolkit for data analysis.

32 . What is the procedure for copying an entire library?

  • Copy statement should be followed by an input data library and an output data library.

33 . Explain COMPRESS data set option?

  • It is used for compressing the data into new output.

34 . Explain VFORMATX Function?

  • It is used to return the format which is assigned with the value of the given Statement.

35 . Explain what is the use of PROC gplot?

  • PROC gplot identifies the data set that contains the plot variables. It has more options and therefore can create more colorful and fancier graphics.

36 . In SAS explain which statement does not perform automatic conversions in comparisons?

  • By using WHERE statements automatic conversions can’t be performed because WHERE statement variables exist in the data set.

37 . Define STD function?

  • Standard deviation will be returned for nonmissing statements.

38 . What is the difference between a format and an informat?

  • Format : A format is to write data i.e. WORDIATE18 and WEEKDATEW
    Informat : An informat is to read data i.e. comma, dollar and date (MMDDYYw, DATEw, TIMEw, PERCENTw)

39 . Define Formats?

  • Instruction used by SAS for writing data values is known as Formats.

40 . Explain PROC SORT?

  • PROC SORT sorts SAS data set by variables so that a new data set can be prepared for further use.

41 . Define RUN-Group processing?

  • RUN-Group processing is used to submit a PROC step using RUN statement without ending the procedure.Interested in a high-paying career in Big Data?

42 . Explain what is SAS informats?

  • An informat is an instruction that SAS uses to read data values. They are used to read, or input data from external files.

43 . How to sort in descending order?

  • By using DESCENDING keyword in PROC SORT code, we can sort in descending order.

44 . What are the special input delimiters?

  • The input delimiters are DLM and DSD.

45 . What are the uses of SAS?

  • SAS/ETS software provides tools for a wide variety of applications in business, government, and academia. Major uses of SAS/ETS procedures are economic analysis, forecasting, economic and financial modeling, time series analysis, financial reporting, and manipulation of time series data.
    The common theme relating the many applications of the software is time series data: SAS/ETS software is useful whenever it is necessary to analyze or predict processes that take place over time or to analyze models that involve simultaneous relationships.
    Although SAS/ETS software is most closely associated with business, finance and economics, time series data also arise in many other fields. SAS/ETS software is useful whenever time dependencies, simultaneous relationships, or dynamic processes complicate data analysis.For example, an environmental quality study might use SAS/ETS software’s time series analysis tools to analyze pollution emissions data. A pharmacokinetic study might use SAS/ETS software’s features for nonlinear systems to model the dynamics of drug metabolism in different tissues.

46 . What function CATX syntax does?

  • CATX syntax inserts delimiters, removes trailing and leading blanks and returns a concatenated character string.

47 . What is the use of sysrc function?

  • It is a function which provides a system error number.

48 . Explain APPEND procedure?

  • APPEND means adding at the end so in terms of SAS we can say adding one sas data set to another sas data set.

49 . What do the put and input function do?

  • Input Function : Character values are converted into numeric values Put function : Numeric values are converted into character values.

50 . What are the features of SAS system?

  • It provides Ipv6 support, new true type fonts, extended time notations, restart mode, universal printing, checkpoint mode and ISO 8601 support.