Speaker 1: Top 48 Statistical Analysis System, SAS, Interview Questions and Answers. For fresh and experienced candidates, AliAziz Quality Education Channel providing you the job best interview related videos so don't forget the subscription button. 1. What is SAS? What are the functions does it performs? SAS means Statistical Analysis System, which is an integrated set of software products. Information Retrieval and Data Management. Writing Reports and Graphics. Statistical Analytics, Econometrics and Data Mining. Business Planning, Forecasting, and Decision Support. Operation Research and Project Management. Quality Improvement. Data Warehousing. Application Development. 2. What is the basic structure of the SAS Base Program? The basic structure of SAS consist of. == Data Step, which recovers and manipulates data. == PROC Step, which interprets the data. 3. What is the basic syntax style in SAS? To run the program successfully, and you have the following basic elements. There should be a semicolon at the end of every line. A data statement that defines your data set. Input statement. There should be at least one space between each word or statement. A run statement. For example, in file h, backslash stat hw backslash your filename dot dat. 4. Explain Data Step in SAS. The Data Step creates a SAS data set which carries the data along with a data dictionary. The data dictionary holds information about the variables and their properties. 5. What is PDV? The logical area in the memory is represented by PDV or Program Data Vector. At the time, SAS creates a database of one observation at a time. An input buffer is created at the time of compilation which holds a record from an external file. The PDV is created following the input buffer creation. 6. What are the data types does SAS contain? The data types in SAS are numeric and character. 7. Which statement does not perform automatic conversions in comparisons? In SAS, the WHERE statement does not perform automatic conversions in comparisons. 8. What is a method to debug and test your SAS program? You can debug and test your SAS program by using obs equals 0 and systems options to trace the program execution in log. 9. What is the difference between Nodjupkey and Nodjup options? The difference between the Nodjup and Nodjupkey is that Nodjup compares all the variables in our data set while Nodjupkey compares just the by variables. 10. Name validation tools used in SAS. For data set, data set name slash debug data set, name slash stmtchk. For SAS macros variables, options, mprintmlogic symbolgen. 11. What does PROC print, and PROC contents do? To display the contents of the SAS data set PROC print is used and also to assure that the data were read into SAS correctly. While PROC contents display information about a SAS data set. 12. What is the use of function PROC summary? The syntax of PROC summary is the same as that of PROC means. It computes descriptive statistics on numeric variables in the SAS data set. 13. What PROC GLM does? PROC GLM performs simple and multiple regression, analysis of variance, ANOVL, analysis of covariance, multivariate analysis of variance and repeated measure analysis of variance. 14. What is SAS informats? SAS informats are used to read, or input data from external files known as FLAD files ASCII files, text files, or sequential files. The informa will tell SAS on how to read data into SAS variables. 15. Name types of category in which SAS informats are placed. SAS informats are placed in three categories. Character informats, $INFORMATW. Numeric informats, informaw.d. Slash time informats, informaw. 16. What function CATX syntax does? CATX syntax concatenates character strings remove trailing and leading blanks and inserts separators. 17. What is the use of PROC plot? PROC plot has more options and can create more colorful and fancier graphics. 18. What is PROC in SAS? In SAS, PROC steps analyze and process data in the form of an SAS data set. It controls a library of routines that perform tasks on SAS data set options such as sorting, summarizing, and listing. 19. What is the SAS data set? A SAS data set is a file consisting of two parts. A descriptor portion. A data portion. 20. List out some key concept of SAS. Some key concept of SAS include. Sort procedure. Missing values. Keep equals, drop equals data set options. Data step logic. Reset to missing, or the retain statement. Log. Sort procedure for creating value formats. Data types. In equals data set option. 21. What is the difference between input and infile? Infile. Input. Infile statement is used to identify an external file. Input statement is used to describe your variables. 22. What the difference between informa and format? Informa, to indicate SAS that a number should be read in a particular format. Format, to indicate SAS how to print the variables. 23. What is factor analysis? Factor analysis is a common term used for a family of statistical techniques associated with the reduction of a set of observable variables in terms of a small number of latent parameters. The main goal of factor analysis is data reduction and summarization. 24. How you can read the variables that you need? You read the variables using input statement with column slash line pointers, informats, and length specifiers. 25. What are the special input delimiters used in SAS? Special input delimiters used in SAS are DLM and DSD. 26. How SAS treats the DSD delimiters? When you define DSD, SAS treats two consecutive delimiters as a missing value and removes quotation marks from character values. 27. What is the good SAS programming practices for processing large data sets? The good SAS programming practices for processing large data sets is to sort them once using FIRST TOPS equals and OBS equals. 28. How to include or exclude specific variables in a data set? To include or exclude specific variables in a data set you can use DROP, KEEP statements, and DATA SET options. 29. How Substra function works in SAS? The Substra function is used to abstract substraying from a character variable. 30. What SAS features do you use to check errors and data validation? To check errors, use the log, and for data validation use things like PROC frequency, PROC means or sometimes PROC print to see how data looks. 31. What are the ways to do a table lookup in SAS? There are 5 ways to do a table lookup in SAS which include PROC SQL, MATCH merging, DIRECT ACCESS, FORMAT TABLES, ARRAYS. 32. How will you generate test data with no input data? You will generate test data with no input data using PUT statement and DATIN NULL. 33. What are the difference between SEAL and FLOOR functions in SAS? The FLOOR returns the greatest integer less than slash equal to the argument. Whereas the SEAL function returns the smallest integer greater than slash equal to the argument. 34. What are the difference between SAS functions and procedures? The difference between SAS functions and procedures is that. Procedures expect one variable value per observation. Functions expect values to be supplied across an observation. 35. How to remove duplicates using PROC SQL? To remove duplicates using PROC SQL use following step. PROC SQL now print. Create table inter.merged1 as. Select distinct asterisk from inter.readin. 36. What are common programming errors committed in SAS? Common programming errors committed in SAS are. Missing semicolon. Not checking log after submitting program. Not using debugging techniques. Not using fsview option vigorously. 37. How to limit decimal places for the variable using PROC means? By using maxdequequals option, you can limit decimal places for the variable. 38. What are the difference between the SAS DATA step and SAS PROCs? SAS DATA step is used to read in and manipulate data. SAS PROCs are subroutines perform tasks on SAS data set. 39. What is the use of stop statement? A stop statement is used to control the continuous looping in set statement. 40. What is run group processing? Run group processing allows submitting a PROC step using run statement without ending the procedure. 41. How to test the debugging in SAS? For debugging in SAS use the DEBUG clause after slash in the DATA statement. 42. How to create a permanent SAS data set? In order to create a permanent SAS data set, there are two steps necessary. Assign a library and engine. Create the data. Make sure to assign both a library, other than work, and data set name to make the data set permanent. 43. What is Slibref? Slibref is a server libref. It specifies the libref that is used by the server to identify the SAS data library when no physical name is determined, and the server libref is different from the client libref. 44. What are the default statistics that PROC means produce? The default statistics that PROC means produce are n, min, max, mean, std dev. 45. What is the command used to find missing values? The command used to find missing values is missing underscore values equals missing, 46. What is the difference between match merge and 1-to-1 merge? A 1-to-1 merge is suitable if both data sets in the merge statement are sorted by ID, and each observation in one data set has a corresponding observation in the other data set. If the observations do not match, then match merging is suitable. 47. What are the scrubbing procedures in SAS? The scrubbing procedures in SAS are PROC sort with Najapki option. It will eliminate duplicate values. 48. What is the use of the %include statement? %include statement reads an entire file into the current SAS program you are running and submits that file to the SAS system immediately.