sas interview question and answers

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SAS Interview Questions for Fresher’s and Experienced Candidates on SAS Basic to Advanced Fundamental and Technical interview Question and Answers on Various topics of SAS

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  • SAS Interview Questions for Freshers and Experienced Candidates on SAS

    Basic to Advanced Fundamental and Technical interview Question and

    Answers on Various topics of SAS Programming. For any type of support on

    SAS Programming or Online Training @ www.vibloo.com

    Skype: info.vibloo Email: [email protected] USA: +1-248-809-1418 IND: +91-40-3296-5222

    www.vibloo.com

  • What is SAS? What are the functions does it performs?

    SAS is an integrated set of software products. The acronym stands for

    Statistical Analysis System.

    Information retrieval and data management

    Writing reports and graphics

    Statistical analysis, econometrics and data mining

    Business planning, forecasting and decision support

    Operation research and Project management

    Quality Improvement

    Data Warehousing

    Application Development

    What is the basic structure of SAS programing?

    The basic structure of SAS are

    Program Editor

    Explorer Window

    Log Window

    What is the basic syntax style in SAS?

    To run program successfully, and you have following basic elements:

    There should be a semi-colon 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 and statement

    A run statement

    What are SAS/Access and SAS/Connect?

    SAS/Access only process through the database like oracles, SQL-server, Ms-

    Access etc. SAS/Connect only use server connections.

    What is the Difference between SCAN and SUBSTR?

    SCAN extracts words within a value that is marked by delimiters. SUBSTR

    extracts a portion of the value by stating the specific location. It is best used

    when we know the exact position of the sub string to extract from a character

    value.

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  • What is Data Step?

    The Data step creates an SAS dataset which carries the data along with a

    data dictionary. The data dictionary holds the information about the

    variables and their properties.

    What is DATA _NULL_?

    The DATA _NULL_ is mainly used to create macro variables. It can also be

    used to write output without creating a dataset. The idea of "null" here is that

    we have a data step that actually doesn't create a data set.

    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.

    What do the put and input function do?

    Input function converts character data values to numeric values. Put function

    converts numeric values to character values.

    Ex: for input: input (source, informat)

    What are the data types does SAS Contain?

    The data types in SAS are Numeric and Character.

    What are the special input delimiters?

    The input delimiters are DLM and DSD

    What is the purpose of using the N=PS option?

    The N=Ps option creates a buffer in memory which is large enough to store

    PS lines and enables a page to be formatted randomly prior to it being printed.

    What is the difference between NODUPKEY and NODUP options?

    The difference between the NODUP and NODUPKEY is that, NODUP compares

    all the variables in our dataset while NODUPKEY compares just the BY

    variables

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  • Mention the validation tools used in SAS?

    For Data Set: Data set name/ debug Data set: Name/stmtchk

    For Macros: Options: mprint mlogic symbolgen

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

    To display the contents of the SAS dataset PROC print is used and also to

    assure that the data were read into SAS correctly. While, PROC CONTENTS

    display information about an SAS dataset.

    Explain what is the use of function Proc summary?

    The syntax of proc summary is same as that of proc means, it computes

    descriptive statistics on numeric variables in the SAS dataset.

    What difference did you find among version 6, 8 and 9?

    Architecture is fundamentally different from any prior version of SAS. In the

    SAS 9 architecture, SAS relies on a new component, the metadata server, to

    provide an information layer between the programs and the data they access.

    Metadata, such as security permission for SAs libraries and where the various

    SAs servers are running, are maintained in a common repository.

    Explain what Proc glm does?

    Proc glm performs simple and multiple regression, analysis of variance

    (ANOVAL), analysis of covariance, multivariate analysis of variance and

    repeated measure analysis of variance.

    Explain what is SAS informats?

    SAS INFORMATS are used to read, or input data from external files known as

    Flat Files ASCII files, text files or sequential files. The informat will tell SAS on

    how to read data into SAS variables.

    Mention the category in which SAS Informats are placed?

    SAS informats are placed in three categories,

    i. Character Informats: $INFORMATw

    ii. Numeric Informats: INFORMAT w.d

    iii. Date/Time Informats: INFORMAT w.

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    www.vibloo.com

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  • What function CATX syntax does?

    CATX syntax concatenate character strings remove trailing and leading blanks

    and inserts separators.

    Explain what is the use of PROC gplot?

    PROC gplot has more options and can create more colorful and fancier

    graphics.

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