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Accounting Information Systems
Marshall B. Romney • Paul John Steinbart
[Oval: Chapter -2- 2] R
Documentation explains how a system works, including the who, what, when, where, why,and how of data entry, data processing, data storage, information output, and system controls.Popular means of documenting a system include diagrams, flowcharts, tables, and othergraphical epresentations of data and information. These are supplemented by a narrative
description of the system, a written step-by-step explanation of system components and interactions.
In this chapter, we explain three common systems documentation tools: data flow diagrams, flowcharts, and business process diagrams.Documentation tools are important on the following levels:
1. At a minimum, you must be able to read documentation to determine how a system works.
2. You may need to evaluate documentation to identify internal control strengths andweaknesses and recommend improvements as well as to determine if a proposed system meets the company’s needs.
3. More skill is needed to prepare documentation that shows how an existing or proposed system operates.
This chapter discusses the following documentation tools:
1. Data flow diagram (DFD), a graphical description of data sources, data flows, transformation processes, data storage, and data destinations
2. Flowchart, which is a graphical description of a system. There are several types of flow
a. Document flowchart, which shows the flow of documents and nformation between departments or areas of responsibility b. System flowchart, which shows the relationship among the input,processing, and output in an information system
c. Program flowchart, which shows the sequence of logical operations a computer performs as it executes a program.
3. Business Process diagrams, which are graphical descriptions of the business processes used by a company Accountants use documentation techniques extensively. Auditing standards require that independent auditors understand the automated and manual internal control procedures an entity uses. One good way to gain this understanding is to use business process models or
flowcharts to document a system, because such graphic portrayals more readily reveal internal control weaknesses and strengths.
The Sarbanes-Oxley Act (SOX) of 2002 requires an internal control report in public company annual reports that (1) states that management is responsible for establishing and maintaining an adequate internal control structure and (2) assesses the effectiveness of the company’s internal controls. SOX also specifies that a company’s auditor must evaluate management’s assessment of the company’s internal control structures and attest to its accuracy. The auditor’s attestation should include a specific notation about significant defects or material noncompliance found during internal control tests. This means that both the company and its auditors have to document and test the company’s internal controls. To do so, they must be able to prepare, evaluate, and read different types of ocumentation, such as business process models and flowcharts.
Documentation tools are also used extensively in the systems development process. In addition, the team members who develop information systems applications often change, and documentation tools help the new team members get up to speed quickly. Documentation is easier to prepare and revise when a software package is used. Once a few basic commands are mastered, users can quickly and easily prepare, store, revise, and print presentation-quality documentation.The documentation tools in this chapter are used throughout the book.
Data Flow Diagrams
A data flow diagram (DFD) graphically describes the flow of data within an organization. It uses the first four symbols shown in Figure 3-1 to represent four basic elements: data sources and destinations, data flows, transformation processes, and data stores. For example, Figure 3-2 shows that the input to process C is data flow B, which comes from data source A. The outputs of process C are data flows D and E. Data flow E is sent to data destination J. Process F uses data flows D and G as input and produces data flows I and G as output. Data flow G comes from and returns to data store H. Data flow I is sent to data destination K.Figure 3-3 assigns specific titles to each of the processes depicted in Figure 3-2.Figures 3-2 and 3-3 will be used to examine the four basic elements of a DFD in more detail.
In Chapters 12 through 16, the basic DFD has been adapted so that it shows internal controls,using the triangle symbol (highway warning symbol) shown in Figure 3-1. The internal controls are numbered and an accompanying table explains the internal control. Users who do
not wish to indicate internal controls simply ignore the triangle symbol.
A data source and a data destination are entities that send or receive data that thesystem uses or produces. An entity can be both a source and a destination. They are represented by squares, as illustrated by items A (customer), J (bank), and K (credit manager) in
A data flow is the movement of data among processes, stores, sources, and destinations.Data that pass between data stores and a source or destination must go through a data transformation process. Data flows are labeled to show what data is flowing. The only exception is data flow between a process and a data store, such as data flow G in Figure 3-3, because
the data flow is usually obvious. In data flow G, data from the accounts receivable file is retrieved,updated, and stored back in the file. Other data flows in Figure 3-3 are B (customer payment), D (remittance data), E (deposit), and I (receivables data). If two or more data flows move together, a single line is used. For example, data flow B(customer payment) consists of a payment and remittance data. Process 1.0 (process payment)
splits them and sends them in different directions. The remittance data (D) is used to update accounts receivable records, and the payment (E) is deposited in the bank. If the data flow separately, two lines are used. For example, Figure 3-4 shows two lines because customer inquiries (L) do not always accompany a payment (B). If represented by the same data flow, the separate elements and their different purposes are obscured, and the DFD is more difficultto interpret.Processes represent the transformation of data. Figure 3-3 shows that process payment (C) splits the customer payment into the remittance data and the check, which
is deposited in the bank. The update receivables process (F) uses remittance (D) and accounts receivable (H) data to update receivable records and send receivables data to the credit manager.
A data store is a repository of data. DFDs do not show the physical storage medium (such as a server or paper) used to store the data. As shown in Figure 3-3, data stores (H) are represented by horizontal lines, with the name of the file written inside the lines.
SUBDIVIDING THE DFD
DFDs are subdivided into successively lower levels to provide ever increasing amounts of detail, because few systems can be fully diagrammed on one sheet of paper. Also, users have differing needs, and a variety of levels can better satisfy differing requirements. The highest-level DFD is referred to as a context diagram because it provides the reader with a summary-level view of a system. It depicts a data processing system and the entities that are the sources and destinations of system inputs and outputs. For example,
Ashton drew Figure 3-5 to document payroll processing procedures at S&S.
The payroll processing system receives time card data from different departments and employee data from human resources. The system processes these data and produces (1) tax reports and payments for governmental agencies, (2) employee paychecks, (3) a payroll check deposited in the payroll account at the bank, and (4) payroll information for management.
Ashton used the description of S&S’s payroll processing procedures in Table 3-1 to decompose
the context diagram into successively lower levels, each with an increasing amount of detail. Read this description and determine the following:
●● How many major data processing activities are involved?
●● What are the data inputs and outputs of each activity (ignoring all references to people,
departments, and document destinations)?
A flowchart is a pictorial, analytical technique used to describe some aspect of an information system in a clear, concise, and logical manner. Flowcharts record how business processes are performed and how documents flow through the organization. They are also used to analyze how to improve business processes and document flows. Most flowcharts are drawn using
a software program such as Visio, Word, Excel, or PowerPoint. Flowcharts use a standard set of symbols to describe pictorially the transaction processing procedures a company uses and the flow of data through a system. Flowcharting symbols are divided into four categories, as shown in Figure 3- 8:
1. Input/output symbols show input to or output from a system.
2. Processing symbols show data processing, either electronically or by hand.
3. Storage symbols show where data is stored.
4. Flow and miscellaneous symbols indicate the flow of data, where flowcharts begin or end, where decisions are made, and how to add explanatory notes to flowcharts. General guidelines for preparing good flowcharts are presented in Focus 3-2.
TYPES OF FLOWCHARTS
Document flowcharts were developed to illustrate the f low of documents and
data among areas of responsibility within an organization. They trace a document from its cradle to its grave, showing where each document originates, its distribution, its purpose,
its disposition, and everything that happens as it f lows through the system. A special
type of flowchart, called an internal control flowchart, is used to describe, analyze,
and evaluate internal controls. They are used to identify system weaknesses or inefficiencies,such as inadequate communication flows, insufficient segregation of duties, unnecessary complexity in document flows, or procedures responsible for causing wasteful delays.Until he automates the other parts of S&S, Ashton decides to process payroll manually.The document flowchart Ashton developed for the manual payroll process at S&S, as described
in Tables 3-1 and 3-2, is shown in Figure 3-9.You can practice creating a document flowchart by drawing one for the comprehensiveproblem, called Accuflow Cash Disbursements Process, at the end of the chapter content (page 93).You can then compare your diagram to the solution at the very end of the
chapter (pages 104–109).You can also read the detailed explanation of how the solution was prepared.
A program flowchart illustrates the sequence of logical operations performed by a computer in executing a program. The relationship between system and program flowcharts is shown in Figure 3-11. A program flowchart describes the specific logic used to perform a process shown on a system flowchart.
Business Process Diagrams
A Business Process Diagram (BPD) is a visual way to describe the different steps or activities in a business process. For example, there are many activities in the revenue cycle. Among them are receiving an order, checking customer credit, verifying inventory availability, and confirming customer order acceptance. Likewise, there are multiple activities involved in the expenditure cycle. Among them are shipping the goods ordered, billing the customer, and collecting customer payments. All of these activities can be shown on a BPD to give the reader an easily understood pictorial view of what takes place in a business process. While BPDs can describe interactions within an entity as well as interactions between entities, the BPDs in the textbook do not document the activities performed by external parties. Thus, a BPD for the revenue cycle will only describe the functions performed by the selling company and a BPD for the expenditure cycle only depicts the activities performed by the purchasing company.The Business Process Modeling Initiative Notation Working Group established standards for drawing BPDs. There are many different symbols that can be used in drawing a BPD. The text uses only a limited set of those symbols, as shown in Figure 3-12, to produce easy to create
and understand BPDs. General guidelines for preparing good business process guidelines are presented in Focus 3-3. In the text, the emphasis on BPDs is less on obeying the rules governing their preparation and more on their clearly communicating the activities involved in the businessprocess being depicted.
Ashton prepared the BPD in Figure 3-13 to document payroll processing at S&S based on the narrative contained in Table 3-1. You can practice creating a BPD by drawing one for the comprehensive problem, called Accuflow Cash Disbursements Process, at the end of the chapter content (page 93).You can then compare your diagram to the solution at the very end of the chapter
(pages 104–109). You can also read the detailed explanation of how the solution was prepared.
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