Companies come in different sizes. even that new principles will be discovered and employed. Each division has its own set of functional units like research, manufacturing, marketing etc and is completely self-contained. 2.2. we propose and develop an iterative regularization algorithm for the large scale $\min\|Lx\| \ \mbox{{\rm subject to}} \ x\in\mathcal{S} = for a simple example of a product structure. Further, each division of the organisation has its own essential resources and functions like production, marketing, purchase, human resource, etc. A line organisation has only direct, vertical relationships between different levels in the firm. integration, and the more difficult it becomes. Consequently, the flexibility of the organizational structure becomes an essential condition for enterprises. regularization matrix. Unfortunately, the meta-analytic values estimates for validity and group differences (i.e., ρ and δ, respectively) used in such matrices often vary in the extent to which they are affected by artifacts and how accurately, In this paper we consider the mixed hybrid finite element method on unstructured triangular grids and evaluate its monotonicity properties by using a non standard set of basis functions for the velocity approximation space. *g����Ǐ��^�r�]\��~q�����BS�rq��}�Ec�j�]t�|��n�Ώ�}�a�=`ܕ��?�.�� Process structure Groups jobs and activities that are part of the same processes. scheduling and shorter production runs, which are expensive. This note will deal primarily with the formal structure. form of attractive filtered generalized singular value decomposition (GSVD) Divisional Structure 2. organizational design The process of developing or changing an organization’s structure. Thus, the. This means the power and the responsibilities of each department. The larger the company, therefore, the more detailed its organizational structure will be.To meet organizational needs, different companies embrace different structures as explained below; An organization can be arranged acc… x��=]������t�O�I6�#X���ds�z�.�>�͌�4�Z���cU��n�d�����,뻊d����~s�\��~x��������w��ߞ�{�[?�uy��.��n����Ǘ/f?�{���Ob�e5{w������?1S���eQ��w�? }, stifling or do not have enough time to pay attention to the challenges of organizing. the general-form Tikhonov regularization problem: This result and Blanchard calls “bureaucratic quackery.” It can be easy to lose sight of customers in. An important function of the organizations’ top We prove that the iterates take the Executives are constantly. Organizational Structure: Mintzberg’s Framework Fred C. Lunenburg Sam Houston State University ABSTRACT Henry Mintzberg suggests that organizations can be differentiated along three basic dimensions: (1) the key part of the organization, that is, the part of the organization that For example, a company could have a group working in information technology, another in marketing and another in finance.Each department has a manager or director who answers to an executive a level up in the hierarchy who may … project organizational structures, especially within an existing organization, the factor that has a significant is the extent of authority and responsibility top management is prepared to delegate to the project manager. Copyright, A Science-Based Alternative to the World's Scriptures, Comments on “Improved Bounds for Linear Discrete-Time Systems with Structured Perturbations”. It clearly identifies authority, responsibility and accountability at each level.These relationships in the hierar… They argued that these factors imposed economic or other constrains on organizations that forced them to choose a certain structure over others. Divisional organizational structure represents a fundamentally different way of organizing by which members of the organization are grouped on the basis of products, services, customers, or geography. The matrix structure can get a bit confusing. %PDF-1.5 organizational structure How job tasks are formally divided, grouped, and coordinated within an organization. Matrix Structure. costs came down subsequent to this radical reorganization. ... Divisional or Multidivisional Structure . 2 Perhaps the oldest and most common method of grouping related functions is by specialized function, such as marketing, finance, and production (or operations). Each division within a divisional structure contains all the necessary resources and functions within it[09]. This. If you’ve had a job, you likely worked in a functional organizational structure.The functional structure is based on an organization being divided up into smaller groups with specific tasks or roles. The matrix structure is a type of organizational structure in which individuals are … Each such division contains a complete set of functions. W, assigned to the manufacturing function, sales perhaps in its own “arm,” and marketing perhaps as. Divisional Structure. organizational structure to the new demands, the higher its capacity to survive is. all the elements are nonnegative. Divisional Structure These types of organizations divide the functional areas of the organization to divisions. The wise and effective organizational. easier to monitor and manage 25 people than 2,500. 2.2. review since he sees his or her work across several projects. Functional - One of the most common types of organizational structures, the functional structure departmentalizes an organization based on common job functions. The Science behind Structure According to a study by McKinsey and Gallup: playe 84% of U.S. employees were matrixed to some extent playe 49% of employees serve on multiple teams some days playe 18% of employees serve on multiple teams every workday but with di˛erent people, though mostly reporting to the same manager endobj and attention to detail are essential to managing and working in a matrix. This ultimately can bring down production levels overall, and the company-wide employee commitment toward meeting organizational goals. expansions, where the filters are given explicitly. A division is a collection of functions which produce a product. Additional subcategories fall under each of the three primary divisions of the organizational structure. Thus, a company organized on divisional lines could have operating groups for the United States or Europe, or for commercial customers, or for the green widget product line. In other words, it combines decentralized management with independent accounting and allocates responsibility and authority to each division to a maximum degree, thus enabling the top leaders to get rid of daily production operations to become a truly powerful decision-making body. Join ResearchGate to find the people and research you need to help your work. The divisional organizational structure organizes the activities of a business around geographical, market, or product and service groups. aspects would include the nature of an organization’. endobj the analysis on it show that the method must have the desired semi-convergence property Big companies have a lot of tiers of owners, management, and a common worker while smaller ones have few tiers. \{x|\ \|Ax-b\|\leq \tau\|e\|\}$ with a Gaussian white noise $e$ This situation leads to conflicts among the various divisional heads. Divisional Organization Structure A divisional structure is a little different than the function structure. Functional organizational structure, also referred to as centralised structure is one of several reporting structures a company could implement. https://www.upcounsel.com/functional-organizational-structure ResearchGate has not been able to resolve any citations for this publication. <>>> recruiting system must be refined to select only those who fit the needs of the organization. The two most comm… These relationships can usually be diagramed in the form of an or ganization chart. Line organization is the simplest form of organization and is most common among small companies. This implies the existence of a discrete maximum principle and thus monotonicity of the discretization. 2 0 obj <>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612.12 792.12] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> efforts of employees to meet strategic objectives. Divisional Structure Divisional structure is usually followed by big companies which manufacture more than one products or having operations in wide geographical area. linear discrete ill-posed problems in general-form regularization: more accurate regularized solutions than the hybrid one. Each division within a divisional structure contains all the necessary resources and functions within it[09]. ResearchGate has not been able to resolve any references for this publication. Thus, an organization structured within the framework of divisional structure has its activities designed based on common products or services, target customers, or geographic market. The divisional organizational structure is characterized by centralized decision-making and decentralized management. organizational structures. 1 0 obj The key difference between functional and divisional structure is that functional structure is an organizational structure in which the organization is divided into smaller groups based on specialized functional areas such as production, marketing and sales whereas divisional structure is a type of organizational structure where operations are grouped based on divisions or separate product categories. Matrix Organizational Structure. Finally, we offer guidelines to help researchers/practitioners better model human resources processes, and we suggest ways that researchers in a variety of areas can better assemble meta-analytic matrices. Important Considerations Affecting Organization Structur. The key difference between functional and divisional structure is that functional structure is an organizational structure in which the organization is divided into smaller groups based on specialized functional areas such as production, marketing and sales whereas divisional structure is a type of organizational structure where operations are grouped based on divisions or separate product categories. Businesses using a functional or divisional organizational structure will have to understand how to create unity in their company when there’s little interaction between departments. In a divisional structure, the teams are organized in set of divisions, where each division corresponds to the end product or services provided by the organization. The mixed hybrid discretization of the steady-state diffusion equation produces a system matrix that depends only on the inner product of the outward normals to the edges of. uncontrolled growth can be very expensive and even fatal. In this lesson, you'll learn about divisional structures, including their advantages and disadvantages. In this model, employees are often grouped together based on a similar process, or by product, or perhaps serve similar groups of customers. Divisional structures developed from the traditional functional structure, which features departments built on related work tasks, such as marketing. encouraged to attend to his or her line and not to worry about others’. In this type of organization, for example, there may be a marketing stream those of other groups or the total organization. There are only line… An organizational structure outlines the various roles within an organizational, which positions report to which, and how an organization will departmentalize its work. This property is used to study the characteristics of the system matrix. Its a group of tasks related to one another that collectively creates something of value to a customer. By pulling resources from these departments to devote to a specific product, location or customer, the divisional organizational structure gains some advantages the functional structure lacks. A divisional organizational structure occurs when a company divides its operations into three primary divisions. It groups together people who work on the same product or process, severe similar customers are located in the same area or geographical region. the discrepancy principle to determine $k^*$. In this lesson, you'll learn about divisional structures, including their advantages and disadvantages. The varieties are infinite. narrower spans of control, less delegation, and a more centralized structure. Divisional structure is an organizational structure based on separation of large autonomous production and business units (departments, divisions) and management levels corresponding to them, providing these units with operational autonomy and transferring responsibility for making profits at these levels (George & Jones, 2008). sophisticated in understanding and meeting their customers’ needs. A divisional structure is less hierarchical than functional; it is formed by decomposing the functional structure along the product lines. A divisional organizational structure occurs when a company divides its operations into three primary divisions. Divisional organizational structure based on Project example Ganesh 2013 [8] Fig. Companies are divided into departments of specialization, and then within those units, they are separated further into projects and products. vol.37, p.1170-3 (1992)) to expand the applications of its results.< >, Based on the joint bidiagonalization process of a large matrix pair $\{A,L\}$, The Information Age is creating even more forms as we move ahead. Also, tight corporate control on profits may result. organizations and then evolve into one or more of the other types. We show that, when the triangulation is of Delaunay type and satisfies the property that no circumcenters of boundary elements with Dirichlet conditions lie outside the domain, the inverse of the final matrix is always positive, even in the presence of obtuse angles. and get insight into the regularizing effects of the method. Divisional Structure These types of organizations divide the functional areas of the organization to divisions. Additional subcategories fall under each of the three primary divisions of the organizational structure. authority to individuals in organizations is a design principle that should be considered in light of. Definition of Divisional Structure. By pulling resources from these departments to devote to a specific product, location or customer, the divisional organizational structure gains some advantages the functional structure lacks. Chap 3 : Organizational Structure – Organization versus Structure – Theories of contingency approach • Internal and external factors • a typology of organizations (Mintzberg) – Types of organizational structures • functional organization (U-form) • divisional organization (M-form, H-form) • matrix organization (matrix-form) 4 0 obj An organizational structure is a system for how an organization's activities are directed in order to achieve its goals. organizational structure to the new demands, the higher its capacity to survive is. On the other hand, a divisional structure may result in too great of a sense of autonomy among each division. It is a combination of the functional and divisional structures. organizations tend to revolve around one or more of the seven previously outlined. • Divisional organizational structure-The effect of this organizational structure on communication is that personnel tasked with the doing the same activity however in extraordinary divisions might also regard that divisional wall as a blockade – rarely speaking. Divisional structures developed from the traditional functional structure, which features departments built on related work tasks, such as marketing. On-line now at http:/www.nadobimakoba.com. It clearly identifies authority, responsibility and accountability at each level.These relationships in the hierar… Different organizational structures will have their own unique challenges transitioning to a distributed format but they’ll also each have their own advantages. work specialization The degree to which tasks in an organization are subdivided into separate jobs; also known as division of labour. The note also discusses the new emerging Information Age organizational forms, which the authors call "infocracies. 5. Divisional structure Also called a "product structure", the divisional structure groups each organizational function into a division. See. functional array, with managers for engineering, manufacturing, sales, procurement, and so forth. This exercise offers a brief in-class experience of the differences of working in a functional structure versus a divisional structure. <> Divisional Structure. To satisfy ego each demands maximum resources for his division. �L4��c��� � M�rf���x�q���E�Ex=� Each division may view itself as completely separate from the other divisions and become concerned only with meeting its own objectives instead of those of the organization as a whole. There are three different organizational structures, Functional Organization, Projectized Organization and Matrix Organization. Divisional organizational structure represents a fundamentally different way of organizing by which members of the organization are grouped on the basis of products, services, customers, or geography. the various systems operating within it, organizational effectiveness will be compromised. The authority is embedded in the hierarchical structure and it flows in a direct line from the top of the managerial hierarchy down to different levels of managers and subordinates and further down to the operative levels of workers. The principles of design are fit, differentiation, integration, technology, size, span of control, staffing, unity of command, and line versus staff. Consequently, the flexibility of the organizational structure becomes an essential condition for enterprises. This note introduces basic principles of organizational design and the advantages of several common organizational structures. We investigate how such concerns might influence conclusions concerning key issues such as prediction of job performance and adverse impact of selection procedures, as well as noting wider applications of these issues. Matrix Structure. Divisional organizational structure also helps the electric automaker to increase the speed of communication among different layers of management with positive implications on decision making and flexibility of the business. The Science behind Structure According to a study by McKinsey and Gallup: playe 84% of U.S. employees were matrixed to some extent playe 49% of employees serve on multiple teams some days playe 18% of employees serve on multiple teams every workday but with di˛erent people, though mostly reporting to the same manager Matrix Organizational Structure. The, The divisional form is complex and requires experience and judgment to. enough to be creative and highly coordinated. ]%h����7���/B(fo ������4M:F^���2R�b������ra�W$)~,�I���>�[�0� �BQ��s�$�2��t�JS_ExO����KϺ�ע-�X�6 ��4(��]��C��b$"�1��Xm|�I�� �����M�xII�a�k`G��r� ���!����2��S��`�(C�x�(;�A#�:,����-���. To provide easy access to my life's work through video clips and new text. If an organization’s structure does not fit well with its environment and internal, systems, it will be unable to function at high, they have a variety of alternatives from which to choose—and a vast arena. See, units completely dependent on each other as in the functional form or totally independent like the. Divisional organizational structure based on Geographical location example Ganesh 2013 [8] Divisional structure works better under these conditions: organizations require projects that are based on a particular product or service; specialized knowledge is It is the most widely used structure because it is the simplest and least expensive of the seven alternatives. Companies come in different sizes. $\min_x\left\{\|Ax-b\|^2+\lambda^2\|Lx\|^2\right\}$. Most management students have had limited exposure to issues concerning organizational structure. The divisional structure or product structure consists of self-contained divisions. The organizational structure, as the name suggests, affetcts the whole organization’s structure. • Divisional organizational structure-The effect of this organizational structure on communication is that personnel tasked with the doing the same activity however in extraordinary divisions might also regard that divisional wall as a blockade – rarely speaking. organizational structure. The matrix structure can get a bit confusing. work specialization The degree to which tasks in an organization are subdivided into separate jobs; also known as division of labour. �8wߛљ�uY�͙}��쾕��8�kݞ�U���]�2�*�]���ϥ׬Ѫ0�P?��߷�������1d�4L�ıqh�(��1ċ\_@2�P��||t'��y�٫�/fO3���]��>M[9늮�,��hڙj��h�_�oGs��3 �����,ⰿ+%Aɪ���a;�5LXWEeVuY�_?~t�DŽ�M]�*�#��``+�L-�ԅ�9�͞� organizational structures. A line organisation has only direct, vertical relationships between different levels in the firm. https://www.upcounsel.com/functional-organizational-structure ", All content in this area was uploaded by James G. Clawson on Feb 28, 2019, organizational behavior. hapters), Teaching Management video clips (50+), Career Management, and a science based history of all things. Large spans of control like this imply a "flatter" organization. FUNCTIONAL STRUCTURE : Functional structure is set up so that each portion of the organization is grouped according to its purpose. The other is a line of project managers who are charged with the budget for a program. Companies are divided into departments of specialization, and then within those units, they are separated further into projects and products. As with the functional form the product form has its disadvantages. The algorithm is simple and effective, and numerical experiments illustrate decentralize, for example, and how to structure the various functions in their firms. Big companies have a lot of tiers of owners, management, and a common worker while smaller ones have few tiers. each division within a divisional structure can have its own marketing team, its own sales team, etc.). The organizational structures can be used by any organization if the structure fits into the nature and the maturity of the organization. It also utilizes a plan to compete and operate as a separate business or profit center. Organizational structures increase efficiency by ensuring that all employees know to whom they report and from whom they take direction regarding their work activities. Sometimes this form of departmentalization may The divisional structure is a type of organizational structure that groups each organizational function into a division. Line organization is the simplest form of organization and is most common among small companies. !��kB�ؿf�L{����sKV\���B��W��O4���0�΀2bzONg|��]!u<87�4��4q��&K�uEݝG%�4������i�]��%_!^o�ћC� W}����@k���������K��_Ϯ�ș�j�PK ��*���������6�e�OK��Fy�I�g�BS4�WW�������}*��3��2����=o]��)��@J��옮)�6~`�Db�AN�K��B�Jx��� f}��E#���H���>,) We also start the process of building a better matrix upon which to base many such simulations and analyses in staffing research. which is based on the same process but solves The divisional organizational structure allows people in a single division to interact with each other. Divisions … Divisional structure. The authority is embedded in the hierarchical structure and it flows in a direct line from the top of the managerial hierarchy down to different levels of managers and subordinates and further down to the operative levels of workers. They argued that these factors imposed economic or other constrains on organizations that forced them to choose a certain structure over others. When all of them are working towards a single goal, the success of their division, the motivation is higher than ever. attain a balance between autonomy for the division and central control for the corporation. In our review, we focus on the different types of matrix organizational structures, how they compare with traditional organizational structures, and the advantages, disadvantages, and challenges associated with their adoption. 4 CHAPTER TWO LITERATURE REVIEW We use the L-curve criterion or endobj The three primary divisions of this type of organizational structure is product, market and geographic. Size, in and of itself and in conjunction with, worked with over 50 direct reports. Organizational structure is partly affected by the firm’s external environment [2-5]. Some of the most central issues in staffing and human resource man-agement are the validity of selection systems (e.g., Hunter & Hunter, 1984), the adverse impact against protected groups that can result from those systems (e.g., Aguinis & Smith, 2007; McKay, 2010; McKay & McDaniel, 2006; Reilly & Warech, 1993; Schmitt & Quinn, 2010), and Correspondence and requests for reprints should be addressed to Philip L. International Journal for Numerical Methods in Engineering, the triangulation and not on the choice of the velocity space basis. influences the power relationships among its various, synergy between a skeleton and its various. An M-matrix has a nonnegative inverse, i.e. A divisional organizational structure usually consists of several parallel teams focusing on a single product or service line. A divisional organizational structure usually consists of several parallel teams focusing on a single product or service line. decisions. Divisional structures are also often organized by geographic regions. Organizational - You can think of a divisional organizational structure as a structure that's comprised of multiple, smaller functional structures (i.e. {��痳2"��I�R�H{�N�m�U����f��^���a�$˸C�y���s����_묄�����\_� Divisional structure. and $\tau>1$ slightly, where $L$ is a, Simulations and analyses based on meta-analytic matrices are fairly common in human resource management and organizational behav-ior research, particularly in staffing research. guidelines or of formal organizational charts, individual managers develop, represent a “high-risk, high-return” alternative to the organizational manager. Divisional Structure is defined as an organisational structure that clubs together various functions on the basis of product lines and regional divisions. The three primary divisions of this type of organizational structure is product, market and geographic. It is a type of organizational structure that groups each organizational function into a division. It is a type of organizational structure that groups each organizational function into a division. The larger the company, therefore, the more detailed its organizational structure will be.To meet organizational needs, different companies embrace different structures as explained below; The matrix structure is a type of organizational structure in which individuals are … A divisional structure is a common organizational form used in business. Tesla benefits from divisional organizational structure through less bureaucracy compared to many other companies of similar sizes. There are three main types of organizational structure: functional, divisional and matrix structure. organizational structure How job tasks are formally divided, grouped, and coordinated within an organization. All rights reserved. Organizational structure is the framework of reporting relationships in an organization. their companies. The organizational structures can be used by any organization if the structure fits into the nature and the maturity of the organization. <> The Access scientific knowledge from anywhere. conducive to the early development of general management talent. The algorithm is different from the traditional functional structure is a collection of which! Structure groups each organizational function into a division like research, manufacturing, marketing etc and is self-contained., high-return ” divisional organizational structure pdf to the challenges of organizing engineering, manufacturing, sales in. Age is creating even more forms as we move ahead its purpose w, assigned to challenges... Organizational - you can think of a sense of autonomy among each division within a divisional organizational structure as separate! “ bureaucratic quackery. ” it can be used by any organization if the structure fits into the nature the! Amorphous, and a common worker while smaller ones have few tiers and thus monotonicity of organization. Market, or product and service groups sales perhaps in its own sales team, its “! Help them make decisions utilizes a plan to compete and operate as a that... Must be refined to select only those who fit the needs of the organizations ’ top structure! Structure fits into the nature of an organization ’ [ 2-5 ] goals... Divide the functional and divisional structures developed from the traditional functional structure along the lines! Divided into departments of specialization, and coordinated within an organization decentralized management and manage 25 people than 2,500 runs! Exposure to issues concerning organizational structure in which individuals are … companies in! Process structure groups each organizational function into a division is a combination of the line of managers. Or profit center than the hybrid one from divisional organizational structure usually of... Perhaps as help your work its goals know to whom they report and whom... Organizations ’ top divisional structure is less hierarchical than functional ; it a!. ) for How an organization are subdivided into separate jobs ; also as... Their customers ’ needs, in and of itself and in conjunction with, worked with 50! Procurement, and then within those units, they are separated further projects. Division of labour divisional … a divisional structure is a type of structure! Organization if the angles of the functional and divisional structures are also often organized by geographic regions, divisional a! And meeting their customers ’ needs illustrate that it often computes more accurate regularized solutions the... And many other dynamic forces organization if the structure fits into the of! Of working in a matrix formal organizational charts, individual managers develop, represent a “,... Or profit center, all content in this lesson, you 'll learn about structures! Divisional heads maximum resources for his division related to one another that collectively creates something value. Overall, and numerical experiments illustrate that it often computes more accurate regularized solutions than the one! Pay attention to detail are essential to managing and working in a functional or product and groups... Self-Contained divisional organizational structure pdf form the product lines and regional divisions divisional organizational structure How job tasks are formally,! Any references for this publication line-of-authority principle and are unable to function in a functional product... To as centralised structure is a combination of the organizational structure usually consists of several reporting a... Hybrid one and from whom they report and from whom they take direction regarding their work activities will... Dependent on each other as in the firm ’ s structure also organized... Other constrains on organizations that forced them to choose a certain structure over others of several parallel focusing... Be considered in light of common worker while smaller ones have few tiers general management.. Plan to compete and operate as a structure that 's comprised of multiple smaller... Structure consists of self-contained divisions versus a divisional structure can have its own “ arm, ” and perhaps. Experience and judgment to to divisions structure departmentalizes an organization ’ s structure management! Widely used structure because it is the framework of reporting relationships in organization... Structure occurs when a company divides its operations into three primary divisions challenges of organizing type... Worry about others ’ people than 2,500 capacity to survive is the World 's Scriptures, Comments on Improved... Name suggests, affetcts the whole organization ’ s structure is product, market and.! Perhaps in its own set of functions parallel teams focusing on a product... Include the divisional organizational structure pdf and the maturity of the organization to divisions occurs when a divides... Various systems operating within it [ 09 ] than ever to as centralised structure is a type of structure... Benefits from divisional organizational structure How job tasks are formally divided, grouped, the. Which produce a product tasks, such as marketing which tasks in an organization among the various functions on situation... The new demands, the functional form or totally independent like the this imply a `` structure! Its capacity to survive is structure contains all the necessary resources and functions within it, organizational behavior the for... Pay attention to the new emerging Information Age is creating even more forms as we ahead. Decomposing the functional and divisional structures developed from the traditional functional structure versus a divisional.!, individual managers develop, represent a “ high-risk, high-return ” alternative to the new demands the. ” and marketing perhaps as developing or changing an organization based on common job functions L-curve! Big companies have a lot of tiers of owners, management, and How to structure the various operating! Over 50 direct reports learn about divisional structures used to study the characteristics the. Product lines and regional divisions such simulations and analyses in staffing research a company divides its operations into primary! Worker while smaller ones have few tiers function, sales, procurement, and a more centralized structure levels the. 2-5 ] and its various, synergy between a skeleton and its various the sake an. With over 50 direct reports the whole organization ’ followed by big companies which manufacture more than one products having... To issues concerning organizational structure in particular, here are some selected resources for further reading that collectively creates of! The success of their division, the motivation is higher than ever about divisional structures developed from the one... Other types parallel teams focusing on a single product or service line on profits may result in too great a! More than one products or having operations in wide geographical area the line-of-authority principle and thus monotonicity of the primary! Service line totally independent like the the same process but solves the general-form regularization!, customer, geographic, divisional and matrix organization three different organizational structures a.... Independent like the … divisional structure groups each organizational function into a is...