Practice Free A00-215 SAS Certified Associate: Programming Fundamentals Using SAS 9.4 Exam Questions Answers With Explanation

In the given DATA step, the do weeks=1 to 3; loop iterates three times for each row in the original WORK.RUN dataset, incrementing the miles value by 5 for each iteration and outputting a row after each increment. However, no output; statement is given within the loop to create the extra rows, which means only the last iteration of the loop will be outputted for each original row. Hence, the miles value for each name will be incremented by 15 (5 miles for each of the 3 weeks).

The original data set WORK.RUN has:

John 16

Mary 20

After the DATA step, it should be:

John 31

Mary 35

Each name appears only once because without an explicit output; statement inside the loop, only the final iteration is outputted. The variable weeks is not retained in the output dataset, as it is not used outside the loop and no output statement is used inside the loop. Thus, option D is correct.

References:

• SAS documentation on DATA step processing, SAS Institute.

Option B is correct. In SAS, variable names must be 1 to 32 characters in length. The other statements about variable names are incorrect:

• A is incorrect because variable names are not case sensitive in SAS.
• C is incorrect because variable names are required when you create a data set; each column must have a unique name.
• D is incorrect because variable names cannot start with a number, though they can start with an underscore or a letter.

References:

• SAS 9.4 documentation on SAS variables.

The correct syntax for a conditional if-then block in SAS that includes a do group for executing multiple statements is:

if condition then do;

statement1;

statement2;

end;

In Option B, the syntax if age<13 then do; opens a do group, and age_Cat='Pre-teen'; and account='No Social Media'; are the two statements inside the do group, followed by an end; statement to close the group. However, there is a typo with the use of dashes instead of equal signs for assignment in the variable statements which seems to be an error, so technically, none of the provided options has the correct syntax without an error. The correct syntax should use equal signs (=) for assignment within the do group:

if age<13 then do;

age_Cat='Pre-teen';

account='No Social Media Allowed';

end;

References:

• SAS documentation on conditional processing with IF-THEN/ELSE statements, SAS Institute.

When creating two SAS data sets with a DATA step, you should name both data sets in the DATA statement. This tells SAS to create two separate data sets from the same DATA step. Using an OUT= option in the WHERE statement or a PUT statement are not correct methods for creating data sets. A SET statement is used to read data into the DATA step, not to create output data sets.

References:

• SAS documentation on the DATA step for creating multiple data sets.

In the DATA step provided, average is calculated using the mean function, which calculates the average of the non-missing values of the variables listed. The variables provided are:

• var1 = 2
• var2 = 4
• var3 = .
• var4 = 6

The mean function in SAS ignores missing values, represented by a period (.). Hence, the average is computed using the non-missing values (2, 4, and 6). The mean of these three numbers is calculated as: (2 + 4 + 6) / 3 = 12 / 3 = 4

Therefore, the value of average is 4.

References:

• SAS documentation on the MEAN function, SAS Institute.

In SAS, the DATA step is a powerful tool that allows programmers to perform a variety of tasks such as reporting, managing, and analyzing data. The DATA step processes data one observation at a time, making it highly efficient for data manipulation tasks. It enables the creation of new datasets, modification of existing ones, and complex data transformations. Additionally, within a DATA step, you can use a wide range of programming statements and functions to calculate new variables, merge or sort datasets, and perform conditional processing. The flexibility and functionality provided by DATA steps make them a fundamental part of SAS programming for handling and preparing data for further analysis or reporting.References: SAS 9.4 Language Reference: Concepts.

In SAS, iterative DO statements are used to repeat a block of statements a specified number of times. These DO statements have a specific syntax that includes initializing a variable, setting an ending value, and specifying an increment (or decrement). The syntax generally follows the pattern: DO variable = start TO end BY increment;

Let’s evaluate each option provided:

A) Do 100 to 1200 by 100;This statement is syntactically incorrect because it lacks a variable to iterate over. An iterative DO loop must specify a variable that will take on each value in the specified range. The correct form should be something like do i = 100 to 1200 by 100;.

B) Do num = 1.1 to 1.9 by 0.1;This statement is valid. It initializes the variable num at 1.1 and increments by 0.1 until it reaches 1.9. This is a typical use of the iterative DO loop for non-integer increments.

C) Do year = 2000 to 2016 by 2;This statement is also valid. It initializes year at 2000 and increments by 2, going through values like 2002, 2004, etc., up to and including 2016. This is a standard use for iterating over years or other sequentially numbered items.

D) Do reverse = 10 to 1 by -1;This statement is valid. It initializes reverse at 10 and decrements by 1 until it reaches 1. Using negative increments is a legitimate approach for counting downwards.

References

• SAS 9.4 Statements: Reference, "DO Statement."
• SAS Support: DO Loop Documentation

Understanding how to properly format DO loops in SAS is fundamental for effectively managing repetitive tasks in your data analysis. Mistakes like those seen in option A can lead to syntax errors, preventing your code from executing. Always ensure that your loops are correctly structured and that each component of the loop is clearly defined.

In SAS, the correct syntax for assigning labels to variables is to use the LABEL statement within a DATA step or a PROC step. Labels are assigned to variables using the format variable='label'. The correct syntax for the LABEL statement is represented by option B.

Here’s the breakdown:

• FName=’First Name’ correctly assigns the label First Name to the variable FName.
• LName=’Last Name’ correctly assigns the label Last Name to the variable LName.
• Each variable and label pair is separated by a space, and the overall statement ends with a semicolon, which is the proper syntax for a LABEL statement in SAS.

Options A, C, and D are incorrect due to various syntax errors like the use of the wrong character for the apostrophe, missing apostrophes, incorrect punctuation, and in the case of option C, an incorrect conjunction ‘and’ which is not used in LABEL statements.

References:

• SAS 9.4 documentation for the LABEL statement: SAS Help Center: LABEL Statement

The correct answer is B: The XLSX engine can read and write data in Microsoft Excel workbooks. This functionality allows SAS users to directly access and manipulate data stored in Excel files using the .xlsx extension. The XLSX engine does not automatically concatenate individual worksheets; instead, each worksheet is accessed separately. Also, it specifically works with files that have the .xlsx extension, not the older .xls format, thus eliminating option C. Option D is incorrect because the XLSX engine requires the correct file extension (.xlsx) in the LIBNAME statement to properly identify and interact with Excel files.References:

• SAS documentation on LIBNAME statement for XLSX engine: SAS Support: LIBNAME Statement

To rename a variable when reading a dataset in SAS, you use the rename= option inside the parentheses following the dataset's name in the set statement. The correct syntax for renaming the variable 'Name' to 'StudentName' is: rename=(oldname=newname). Therefore, the correct option is A, which correctly places the old variable name 'Name' first, followed by an equal sign, and then the new variable name 'StudentName'. The parentheses enclose the rename operation, and it is correctly nested within the set statement.

References:

• SAS documentation on the RENAME= data set option, SAS Institute.

The program fails because option C is correct: you must include the dataset height2 in the DATA statement. The DATA step is trying to write to a dataset named height2, which has not been defined in the DATA statement. The correct syntax to create two datasets in one DATA step is to list them both in the DATA statement like so:

data height1 height2;

The use of numbers in dataset names is not a problem in SAS, nor is outputting to different data sets within a single DATA step. Additionally, using two different DATA statements for HEIGHT1 and HEIGHT2 is not required and is not the cause of the failure.

References:

• SAS documentation on the DATA statement and creating multiple data sets.

The DROP statement during the compilation phase of the DATA step flags variables in the Program Data Vector (PDV) to be dropped when the data set is output. This means that although the variables exist in the PDV during the DATA step execution, they will not be written to the output data set. The DROP statement does not affect the order of variables (which is the purpose of the ORDER= data set option), nor does it remove variables from the input data set or prevent them from being created in the PDV.

References:

• SAS documentation on the DROP statement.

In SAS, the SUBSTR function is used to extract a substring from a character string. The function syntax is SUBSTR(string, position, length), where:

• string is the variable or string literal you want to extract the substring from.
• position is the starting position of the substring within string.
• position starts counting at 1 in SAS, not 0 as in some other languages.
• length is the number of characters to extract.

For the value of date provided ("02Apr2019"), we want to extract the year, which is the four characters at the end of the string.

Here's how each option would work given the string:

A) year=substr(date, 7, 4);This starts at the 7th character of the string ("2019") and extracts 4 characters, which correctly represents the year.

B) year=substr(date, 4, 6);This starts at the 4th character ("Apr2019") and would extract 6 characters, which gives us "Apr201", not just the year.

C) year=substr(date, 6, 4);This starts at the 6th character ("r2019") and would extract 4 characters, resulting in "r201", which is not correct.

D) year=substr(date, 4, 7);This starts at the 4th character and would extract 7 characters, resulting in "Apr2019", which is the whole string from the 4th character to the end, not just the year.

The correct answer is A, as it extracts the four-digit year from the end of the string.

References:

• The SAS documentation on the SUBSTR function, which details how to use it for extracting parts of strings.
• SAS programming tutorials that often provide examples of common functions like SUBSTR for string manipulation

In SAS, the FORMAT procedure (PROC FORMAT) allows users to create custom formats that can be used to change the way data is displayed without altering the data itself. The VALUE statement within PROC FORMAT is a key component of this procedure.

The VALUE statement can indeed create both numeric and character formats, which is why option C is correct. Numeric format names typically do not start with a $ sign (this is reserved for character format names), and the keyword UNKNOWN is not a part of the VALUE statement syntax; it is used in a different context within PROC FORMAT, specifically for handling undefined data values when using custom formats.

Moreover, the LIB= option is not used within the VALUE statement. The LIB= option is used at the PROC FORMAT level to specify the library where the formats should be stored or from which they should be read.

References

• SAS 9.4 documentation for the PROC FORMAT and VALUE statement.
• "SAS Formats and Informats." in "Step-by-Step Programming with Base SAS 9.4" from the SAS Institute.

In the provided program, there are six distinct SAS statements:

• data FemaleStudents; - Data step beginning
• set sashelp.Class; - Set statement
• where Sex="F"; - Where statement
• Classroom="Red Room"; - Assignment statement
• run; - Run statement to execute the data step
• title "Female Students in Red Room"; - Title statement

Note that the proc print and the second run; statement are part of another PROC step to print the results and hence are not counted in this particular count. The final title; statement is used to clear the title setting and does not count as part of the program statements being asked about.

References:

• SAS 9.4 Language Reference: Concepts, "DATA Step"
• SAS documentation on "TITLE Statement"

The correct answer is D. This option uses the PROC PRINT procedure, which is used to print SAS data sets. The format statement within PROC PRINT temporarily assigns a format to a variable for the duration of the PROC PRINT step. Here is how it works:

• data=sashelp.shoes; tells SAS which dataset to print.
• Format sales comma12.; temporarily assigns a comma format to the sales variable, making it easier to read, especially if the numbers are large. The comma12. format adds commas for thousands, millions, etc., and displays the number in a field that is 12 characters wide.
• The format is only applied for the duration of the PROC PRINT step and does not permanently change the dataset.

The other options are incorrect for the following reasons:

• Option A attempts to use a PROC FORMAT step, which is for creating custom formats, not for assigning formats to variables in a dataset.
• Option B uses a DATA step which could permanently assign the format to the sales variable if it were syntactically correct (it should be set sashelp.shoes; instead of Set sashelp,sheoes;).
• Option C mentions PROC CONTENTS which displays metadata about variables in a dataset and does not have the capability to assign formats.

References:

• SAS 9.4 documentation for the PROC PRINT statement: SAS Help Center: PROC PRINT

When using a BY statement in a DATA step, SAS creates two temporary variables for each BY variable: FIRST.variable and LAST.variable. These are used to indicate the beginning and end of each BY group.

For Ellen's observation:

• First.State=1 because this is the first occurrence of the state "OH" in the dataset when sorted by the state variable, which makes it the beginning of a new group for "OH".
• Last.State=0 because Ellen is not the last observation

for the state "OH" group. In the given dataset snippet, there appears to be only one observation for the state "OH", but since the data is sorted by state, and we don't see another "OH" below Ellen, we can deduce that Ellen's observation is not the last "OH" observation in the entire dataset. If there were no more "OH" observations following Ellen's, then Last.State would be 1.

The FIRST.variable is set to 1 for the first observation in each BY group and 0 for all other observations in the group. Conversely, LAST.variable is set to 1 for the last observation in each BY group and 0 otherwise. Since we're assuming that the dataset is larger than the snippet shown, and the data continues beyond what is visible, we must assume there are more observations for "OH" unless indicated otherwise.

References

• "SAS 9.4 Language Reference: Concepts." SAS Institute Inc.
• "BY-Group Processing" in "SAS Programming 1: Essentials" course material, SAS Institute.

In the given statement, BirthDate = 15DEC2005’d;, the 'd' denotes a SAS date constant, which is a numeric value representing a specific date. SAS date values are stored as numeric variables counting the number of days from January 1, 1960. Therefore, BirthDate is a numeric variable, making option B correct. This constant does not represent a character string (eliminating A), and the byte size of any numeric variable in SAS is 8 by default, not 9 (eliminating C). There is no syntax error in the statement (eliminating D).

References:

• SAS documentation on dates, times, and datetime values, SAS Institute.