2 Principles of Management and application in Library and Information Centres management

Prof H. R. Chopra

I. Objectives

The objectives of the unit/module are, to:

Discuss about the various theories of management,
Explain the need for managing library organizations,
List out the principles of management,
Describe the role of principles of management in an organization,
Mention the three levels of library management, and apply the management theories and principles to management of library organizations.

II. Learning Outcome

After going through this unit/module, you would learn about the different approaches to management, these include: traditional approach, empirical approach, human behavioral approach, decision theory approach, mathematical approach, socio-technical systems approach, contingency approach, and operational management approach. You would also gain knowledge of the principles of scientific management (Taylor’s principles) and how the general management and scientific management principles are applicable to libraries.

III. Structure of the Module

1. Introduction

2. Approaches to Management

2.1 Traditional Approach

2.2 Empirical Approach

2.3 Human Behavioral Approach

2.4 Decision Theory Approach

2.5 Mathematical Approach

2.6 Socio-Technical Systems Approach

2.7 Contingency Approach

2.8 Operational Management Approach

3. Principles of Scientific Management

3.1 Taylor’s Principles

3.2 Fayol’s Principles (General Principles of Management)

3.3 Barnard’s Principles

4. Characteristics of “Not- For-Profit” Organisations

5. Management of Libraries and Information Centres

6. Role of Principles of Management

7. Summary

8. References

1. Introduction

Principles and theories provide the framework of science. These are believed to be fundamental truths. These explain the relationship between two or more sets of variables. Principles of management are derived from the working of industry, government, human psychology and social theories. Knowledge of the basic principles and theories of management helps in practicing management efficiently and effectively. With the development of management thought over the period of time, various approaches for management analysis have been developed. These approaches are known as styles or patterns of managerial analysis or schools of management thought.

2. Approaches to Management

There are two extremes of management style, namely: “Authoritarian” style and “Democratic” or “Participative” style. Authoritarian style is one characterized by reliance on authority-obedience relationship to get the work done. In this approach, there is a rigid adherence on defined lines of command and centralized decision making. But in Democratic or Participative style, there is sharing of responsibilities, reliance on the employees’ own willingness to take whatever actions required of them. It involves a high degree of employees’ participation in decision making. These are two basic styles at two extreme levels on the combination of which different management approaches work and different kind of managers originate. Each school of thought employs different beliefs, views and formats. Some of these schools are relatively broad in their scope, while others tend to restrict to relatively specialized areas. Each style has some merits over the other. But there does not seem to be any rational basis for choosing one style over the other. There is neither complete agreement over the number of approaches nor does clarity about what a particular approach suggest. That is why Koontz has called this situation as “management theory jungle”. There are contradictions in various schools of management thought. As such study of a single approach in studying the management is not sufficient. Major approaches to management or schools of thought are as follows:

2.1 Traditional approach

This is also known as “School of Custom”. It is one of the most commonly followed approaches for management of organizations. Many principles given by Henry Fayol underline the basic philosophy of this school. There are four fundamental characteristics in the traditional style:

The functions of management, such as planning, organizing, motivating and communicating are capable of being defined, emphasized and studied;
There are principles or fundamental truths about organizing and management and these are very important in clarifying the study of management and in improving managerial practice;
The principles of management derived from the study of management should be the starting point for research and should produce even more useful managerial theory; and
Management is to a great extent an art concerned with the application of certain principles that are only to a certain degree based on scientific principles.

This approach analyses management as a universal activity and environment has a great impact on the management and mangers.

2.2 Empirical approach

This approach is based upon the idea that management process may be analyzed but such analysis must be based on the past experiences. It is also known as case approach or management experience approach. The major contributors of this approach are Earnest Daley, Mooney and Reiley, Urwick and other management practitioners, who opine that management is a study of managers in practice. The intention of studying experience is to draw generalizations and to develop means of teaching experiences to other practitioners and students. Attempts are made to duplicate successful experiences while avoiding the unsuccessful ones. The major features of this approach are:

Management is basically a study of managerial experiences and can be taught best by case study method;
Managerial experience can be passed from one practitioner to another or to the students of management for continuous increase in the knowledge of management; and
It is the study of success and failures in the application of management techniques by managers in their practice.
It involves Studying about a large number of experiences so that some sort of generalizations can be possible.

2.3 Human behavioral approach

Major resource within any organisation is the human resource. Its behavior towards work can be modified to fulfill the management goals as management involves getting things done with and through people, so the study of management must revolve around human behavior. It is also called “Human Relations”, “Leadership” or “Behavioral sciences” Approach. As it involves human behavior, it can be divided in two groups: first, “Interpersonal Behavior Approach”, which is based on individual psychology; and second, “Group Behavior Approach”, which relies on social psychology and emphasizes on organizational behavior. The main assumptions of Human Behavioral Approach are as under:

As management is a process of getting things done by people, managers should understand human behavior;
Motivation and good human relations should be the base for better productivity;
Motivation, leadership, communication, participative management and group dynamics are the major themes of this approach.

2.4 Decision theory approach

Its focus is on the concept of analyzing the situations and problems in order to make decisions. Manager is the decision maker and organization is the decision making unit. So the basic problem in managing is to make rational decision. The major contributor of this approach is Simon who gave the following assumptions:

– Management is essentially a decision making process;

– The members of the organisation are decision makers and problem solvers;

– Organisation can be treated as a combination of various decision centres; and

– Quality of decision affects the organizational effectiveness.

In the case of libraries and information centres for planning a new building, for providing special services to the clientele or for making provisions for special members, all these activities require careful analysis and decision making, keeping in view the library budget, equipment and the staff.

2.5 Mathematical approach

It is also known as “Quantitative Measurement Approach” or “Management Science Approach”. It visualizes management as a logical entity, the action of which can be expressed in terms of mathematical symbols, relationship and measurement data. The major features of the approach are as under:

Management is regarded as the problem solving mechanism with the help of mathematical tools and techniques;
Management problem can be described in terms of mathematical symbols and data. Thus every managerial activity can be quantified;
This approach covers decision making, systems analysis and some aspects of human behavior; and
Operations research, mathematical tools, simulation models, etc. are the basic methodologies to solve managerial problems.

This approach can be applied more appropriately where measurement is easy. In case of libraries and information centres, the work of technical processing section can be measured easily, where the measurable units are: a book or a bibliographic unit, etc.

2.6 Socio-technical systems approach

According to this approach, for solving organizational problems, it is not enough to have cooperative social systems alone, but technical systems (i.e., methods and machines) should also be supportive and interactive. Contributed by E.L. Trist, this approach has the following main features:

An organisation is a combination of both social and technical systems which interact among themselves;
Social system of the organisation is governed by the social laws as well as by psychological forces; and
Technical system is governed by technological forces operating in the organization like physical setting of work, rules, proceedings, etc.

In the libraries and information centres, this approach is very much applicable where cooperative social systems are supported by the defined methods, procedures, machines and other equipment for solving the organizational problems from time to time.

2.7 Contingency approach

It is also known as “Situational Approach”. The basic idea of this approach is that there cannot be a particular management action, which will be suitable for all situations. In fact an appropriate action is one which is designed on the basis of external environment as well as internal needs. This approach has the following features:

Management action is contingent on certain actions outside the system or sub-systems, as the case may be;
Organizational action should be based on the behavior of action outside the system so that organisation should be integrated with the environment; and
Because of the specific organisation-environment relationship, no action can be universal. It varies from situation to situation.

This approach is applicable in almost all sections of the libraries and information centres, where decisions are taken keeping in view the internal needs as well as the external environment.

2.8 Operational management approach

This approach is based upon functions of managers in the organisation, commonly known as management process. That is why it is also known as “Management process Approach”. It is frequently followed in understanding management. Major features of operational management approach are:

Management is the study of what the managers do. It emphasizes on the management factors and various concepts and principles involved in performing these functions
Management functions are universal irrespective of the type of organisations or level of management in an organisation ;
The conceptual framework of management can be constructed on the basis of the analysis of management process ; and
The central core of managing revolves around planning, organizing, staffing, directing and controlling, which are the basic functions in management irrespective of the kind of organisation.

Operational management approach is entirely suitable and applicable in case of all types of libraries and information centres.

3. Principles of Scientific Management

The term “Scientific Management” was first of all given by Louis Brandeis in 1910. According to him, the workers in the organisation are economically motivated and they would do their best if they are rewarded financially. The emphasis is on maximum output with minimum strain, eliminating waste and inefficiency.

3.1 Taylor’s principles

Sbsequently, Frederick Winslow Taylor, an American, who is considered to be the father of scientific management, gave the fundamental principles, underlying the scientific approach to management, which is given below:

Replacing the rule-of-thumb method with science by finding the most efficient way;
Obtaining harmony in group action rather than discord;
Achieving cooperation of human beings rather than chaotic individualism;
Working for maximum output rather than restricted output; and
Developing all workers to the fullest extent possible for their own and the company’s highest prosperity.

Efficiency was the central theme of Taylor’s philosophy. He advocated assignment of supervisors by ‘function’, i.e., one for training, one for discipline, etc. He was interested in ascertaining how to get more workouts of workers whom he considered to be naturally lazy. According to him, this attitude was fostered by poor management. He observed that when an energetic person works with a lazy person for a few days, the former also becomes lazy, thinking “why should I work hard when the lazy fellow gets the same pay that I do and does only half as much work”. Taylor proposed using scientific research methods to discover the best way to perform a job. He felt that faster work could be assured only through enforced standardization of methods; enforced adaption of the best instruments available for the work; adaption of good hygienic working conditions; and enforced cooperation.

3.2 Fayol’s principles (general principles of management)

Henry Fayol was of the opinion that the principles of management are flexible. Based on his experience, he listed fourteen General Principles of Management, which are discussed below.

i. Division of work or Specialization

There should be a clear division of duties. Breaking jobs into smaller pieces leads to specialization. Management should be separate and distant. This promotes efficiency in the organisation. The supervisor has a better control because of dealing with a smaller range of activities for each person. In a library, the division can be by type of service or by type of material. Regardless of method, it is important to consider very thoughtfully the objectives and direction of the unit.

ii. Authority and Responsibility

The authority that individuals’ possess should be equal to their responsibility. Anyone responsible for the results of a task should be given the authority to take the action necessary to ensure its success. Responsibility cannot be completed in the best manner unless there is proper level of authority behind it. We can say that authority and responsibility must go together. If one is responsible for the result of task, the person should have the authority to take necessary action to ensure its success. This seems obvious but very often only the responsibility is delegated and not the authority.

iii. Discipline

It is necessary to have clearly defined limits of the acceptable behavior. Everyone in an organization should know as to what is acceptable and what is not acceptable when a rule is violated, the punishment given should be applied equally and fairly by someone who is competent and understanding. Nothing can be achieved without a level of discipline between workers and management. Discipline requires good supervision at all levels. This is applicable in case of libraries and information centres also. This principle is often difficult for a supervisor to apply because there is a tendency of leniency and human relations factors. There should be clear rules and complete obedience of behavior in the best interests of the organisation.

iv. Unity of Command

An employee should receive orders form only one supervisor in order to avoid confusion and conflict. It should be clear in the organisation as to whom a person would be responsible for a given task. In a library, the work of collection development, technical processing and reader’s services are inter-related, involving more than one supervisor. If all of them give the orders separately, it can lead to utter confusion. Hence in such a situation, these supervisors should have consensus and only one person should give the instructions or orders. Unity of command is very important for the successful functioning of libraries and information centres too.

v. Unity of Direction

There should be only one head and one plan, in order to ensure a coordinated effort. All activities that have the same objectives should be supervised by one person. A body with two heads is a monster and has difficulty in surviving. There are a number of interacting variables in a given job situation which, sometimes, cannot be avoided, but there should be minimum line of authority for a given task. For example, in libraries, the bibliographic checking unit should have one supervisor as this work is performed in two departments, namely: acquisition department and technical department. This principle ensures efficiency, economy and uniformity.

vi. Subordination of Individual Interest to General Interest

The employees should place the organization’s concerns before their own. In other words, the individual interests should be subordinated over the general interest of the organisation. Sometimes, it is difficult in certain situations in the organisation. But if this principle is strictly adhered to, would lead to general well-being of the workers in an organisation.

vii. Remuneration of Personnel

The pay or wages for work must be fair and adequate which ensures satisfaction for both the employee and the employer. In a library, the task should be identified first and thereafter, the appropriate staff should be recruited or hired at the established salary or remuneration. It is not a good idea to find the person who can do the job at the lowest possible salary. This can lead to lowering the quality of work or service in the library.

viii. Centralization

Centralization is the most desirable arrangement within an organisation. Both formulation of policy and the generation of basic rules and procedures ought to be centralized. Decisions may be taken at lower or local level but within the framework established by the central authority. Many libraries adhere to this principle rather strongly. This leads to consistency, uniformity and efficiency.

ix. Scalar Chain

It is also known as Lines of Command. In an organization, each position is part of a vertical chain of authority, i.e., The Scalar Chain. Communication should move up and down according to this chain of command. The organizational hierarchy must be formalized and it should reflect the flow of authority and responsibility. In libraries and information centres, the hierarchy is Librarian/ Director (overall head), Deputy Librarians/Deputy Directors (divisional heads), Assistant Librarians/ Assistant Directors (Sectional Heads) and so on.

x. Order

The relationships between various units must be established in a logical and relational manner, so that these units work in harmony. In order to avoid conflicts, there should be a right place for everything and everyone in the organisation for its successful working.

xi. Equality

Equality of treatment must be taken into account in dealing with the employees. Justice should be tempered with kindness. Loyalty and sincerity can be elicited from the employees only when the manager/ supervisor deal with the individual as a person. The persons at the equal level should not be treated individually but as a group.

xii. Stability of Tenure of Personnel

Long term stability for workers is good for an organisation. A high turnover rate is expensive for an organisation. Turnover rate is expensive for an organisation. Turnover is both a cause and an effect of bad management. One way of evaluating the effectiveness of a manager/supervisor is to examine the turnover (absenteeism) rate of persons working under the manager. A low turnover rate may or may not mean that the individual is a good manager. But a high turnover and absenteeism rate indicates that there is a problem and that the manager/supervisor has failed to take corrective measures. A person who is often absent can create bottlenecks in the flow of material, hindering efficiency of the organisation as whole. Such employee often costs the organisation far more than his/her salary. Every time an employee leaves, there is a significant organizational cost. Time and money are spent on recruiting, selecting and training. As such stability of the staff is very important and must be given due consideration

xiii. Initiative

Subordinates should be encouraged to give new ideas and take initiative to propose new plans, which should be undertaken after careful review and consideration. In order to stimulate initiative, incentives and rewards should be established in all type of organizations including libraries.

xiv. Esprit de Corps

Team spirit should be maintained among the individuals within the organisation. There should be complete harmony among the workers in the organisation. Strong sense of morale and unity should be developed among the staff members.Communication is the key to a satisfied working group in the organisation. According to Fayol, viable organizations in times of crisis approach their problems as a team.

As one can see, all the above mentioned general principles of management propounded by Fayol have validity for all types of libraries and information centres also. These principles are being practiced by the modern managers too to achieve efficiency in the concerned organization.

3.3 Barnard’s principles

Chester I. Barnard viewed that the task of executives (mangers) was of maintaining a system of cooperative effort in a formal organisation. The logic of this analysis can be seen in the following steps:

i. Physical and biological limitations of individuals lead them to cooperate and work in groups;

ii. The act of cooperation leads to the establishment of cooperative system, in which physical, biological, personal and social factors or elements are present;

iii. Any cooperative system may be divided into two parts: organisation (which includes only the interactions of people in the system) and other elements;

iv. Organisation can be also be divided into two kinds: ‘formal’ organisation (which is consciously coordinated social interactions that have a deliberate and joint purpose) and ‘informal’ organisation (which refers to those social interactions without a common or consciously coordinated joint purpose);

v. The formal organisation cannot exist unless there are persons who are able to communicate with one another, are willing to contribute to group action, and have a conscious common purpose;

vi. Every formal organisation must include the following elements:

system of fictionalization so that people can specialize,
a system of effective and efficient incentives that will induce people to contribute to group action,
a system of power which will lead the group members to accept the decisions of executives, and
a system of logical decision making.

vii. The executive functions enter the process through the work of the executive in integrating the whole and in finding the best balance between conflicting forces and events; and

viii. To make the executive effective requires a high order of responsible leadership.

The above mentioned principles of management given by Barnard are based on social systems approach , concentrating on major elements of the managerial job, emphasizing on decision making and leadership.

Keeping in view the management theories, principles and procedures, it is obvious that these are very much relevant in managing libraries and information centres also. Yet it is very important to note that the libraries are basically paternalistic, service oriented and not- for- profit organisations. In fact, it is that part of management which is called ‘Service-management’, which is more important to libraries than the management of industrial, commercial and profit oriented organisations.

4. Characteristics of “Not- For-Profit” Organisations

The basic characteristics of services rendered by the ‘not -for-profit’ organizations are as under:

Intangibility: The services may not directly appeal to the services of the customers;
Inseparability: The services are generally produced in the presence of the customers. In other words, there is customer participation in the service production. As such the service production and consumption are inseparable;
Heterogeneity: The services rendered cannot be fully standardized. As a result, there would be variations in the quality of services rendered to different customers; and
Perishability: The services, many times, cannot be stored and an inventory is developed for later physical distribution.

In addition to the above four characteristic of the not- for- profit organisations, there are some other characteristics also which are as follows:

It is difficult to measure and compare the performance of service organisations;
It is equally difficult to inspect quality, determine and implement specifications, take samples and try in advance and also determine the cost of a service;
The relationship between cost (input) and benefit (output) is blurred;
There is no title or ownership transfer when a service is rendered;
Service organisations are labor and equipment intensive and are dominated by professionals;
Excellence is rare and mediocrity common, and the dissatisfaction is rarely conveyed by the customers;
Service organisations are generally small and operate at a single location; and
Market forces play a less significant role in service organisations

5. Management of Libraries and Information Centres

Management of libraries and information centres as services organizations (i.e., not-for-profit organisations) is accomplished by a combination of basic management functions and skills as discussed earlier. We can think of three important roles for a library manager as under;

Interpersonal Role: (a) As figurehead with duties of a ceremonial nature, (b) Leading role, and (c) Liaison role
Informational Role: (a) Perpetually scanning and monitoring the information, (b)
Decisional Role: (a) As entrepreneur looking for new ideas and adopting them for change, (b) Solving the unanticipated problems and handling disturbances, (c) Resources allocation role of dividing work and delegating the authority, and (d) Negotiator role

Modern libraries and information centres are not merely store houses of knowledge and information, but are also live and active institutions involved in a vital service to the society. Today, knowledge and information are considered as important as energy and biotechnology. As such these have to be taken care of and managed very well. Therefore, scientific management theories, principles and practices are increasingly being applied to manage the libraries and information centres to provide effective and quality service to the clients.

Now-a-days, management principles and techniques are being used in the libraries and information centres for a variety of functions such as: information products and services; document delivery; information and documentation services (such as current awareness service, selective dissemination of information service, indexing service, abstracting service, clipping service etc.); planning and plan implementation, forecasting evaluation of operations, budgeting, house-keeping routine operations; and general management.

Today’s managers face a number of challenges. According to Stueart and Moran, management presents great opportunities and allows the manager to make changes in the libraries and information centres. There is a dire need of people who are both willing and able to serve as managers in order to ensure the success of libraries and information centres in the future.

6 .Role of Principles of Management

Principles of management are theoretical in nature. When these are put into practice,there is a tremendous impact on the functioning of the organisation. As these increase efficiency and lead to better results. According to L.M. Prasad, the need and importance of management principles can be visualized as follows:

i. To Increase the Efficiency

As the principles of management are based on experience and are established, these lead to efficiency in the working of the organisation. The managers can understand the problems in a better way. Principles are time tested. As such there is no need of hit and trial any more, costly trials can be avoided. However, certain modifications can be made while applying the management principles, keeping in view the environment, as per situation and need of the organisation. Thus, the efficiency and effectiveness in the organisation is definitely increased.

ii.To crystallize the Nature of Management

Without the knowledge of management principles, it is difficult to analyze the management jobs and know the managerial functions. As such management principles, procedures, rules and methods are necessary to crystallize the nature of management and to train the future managers.

iii. To Carry on Research

When we have fundamental principles, these mark the basis for further research. In the absence of such principles, future research becomes very difficult. It is only due to these principles of management that lots of empirical research is being carried out in all areas of management during the recent years all over the world.

iv. To Attain Social Objectives

Management deals with people and is a part of the society. It takes input from the society and gives output to the society. Thus the standard of the society depends upon the quality of management. In order words, managerial principles play an important role in improving the quality of life of people in the society.

v. To take Realistic View of the Problem

A manager comes across many problems while managing the organisation. If he knows and understands the principles of management properly, he can take a more realistic view of the problems and find their solutions appropriately.Thus, it is evident that understanding of management principles enables the managers to manage the organisation more efficiently. In case of management of libraries and information centres also, this holds good. Knowledge and application of principles of management lead to better planning, better staffing and better organisation. It leads to effective and efficient management. The satisfaction rate amongst the library staff as well as the library users is much higher. As such the management principles play a very important role in increasing the efficiency in the use of human as well material resources in the organisation like libraries and information centres.

7. Summary

A library is an organization that is usually managed by two or more people who interact efficiently and effectively to provide information to their users. For running any organization in an effective manner, efficient management process is required and for this we must follow management theories and principles which lead to a sound theoretical base. The Principles of Management are the essential, underlying factors that form the foundations of successful management. Management principles are guidelines for the decisions and actions of library managers. These are derived through observation and analysis of events faced in actual practice.

In this module, we have discussed various theories of management that include traditional approach, empirical approach, human relations approach, decision theory approach, etc. Principles of management as proposed by various management experts have also been covered. When principles of management are put into practice, there is a tremendous impact on the functioning of the organisation. As these increase efficiency and lead to better results.

8. References

1. Bryson, Jo. Effective library and information centres management. Aldershot, England : Grower, 1990.

2. Encyclopedia of management. New Delhi: Crest Publishing House, 1999.

3. Evans, G. Edwards. “Management education for archivists, Information Managers and Librarians: Is there a global core? Education for Information. Vol 2, Dec- 1984, pp 295-307.

4. Katz, Robert “Skills of an effective administrator”. Harvard Business Review. Vol. 52 Sept- Oct., 1974. pp. 90-102.

5. Narayana, G.J. Library and information management. New Delhi: Prentice Hall of India, 1991.

6. Plaunkett , Warren R, and Attner , Raymond F. Introduction to management. 2nd ed. Boston: Kent Pub. House, 1986.

7. Simon, Hebert A. The New science of management. Englewood: Prentice Hall, 1977.

8. Tripathi, P. C. and Reddy, P.N. Principles of management. 2nd ed. New Delhi: Tata McGraw- Hill 1991.

Learn More:

Glossary

Authoritarian Style	The assumption that the power of leaders is derived from the position they occupy and that people are innately lazy and unreliable
Chaotic	A condition or place of great disorder or confusion
Contingency	A theory that consider an organization’s objectives environment and leadership skills, an interacting and affecting the effectiveness of a leader. Contingency, model of leadership developed by Fiedler, predicts the success of task oriented and relationship
Entrepreneur	A person who undertakes or controls a business or enterprise and bears the risk of profit or loss.
Framework	A structure made of parts joined to form a frame.
Harmony	Agreement of feeling or sentiment; accord, peace.
Heterogeneity	Composed of different elements or constituents; not homogeneous
Intangibility	Something intangible, especially an asset that cannot be perceived by the senses
Integrated	Designed or characterised by a personality in which the component elements combine harmoniously.
Interpersonal	Pertaining or involving a relationship between people
Motivation	Arousing the desire in the minds of workers to give of their best to the enterprise i.e. an act of stimulating or inspiring workers.
Paternalistic	A practice of treating or governing people in a fatherly manner, especially by providing for their needs without giving them rights or responsibilities
Perishability	Subject to destruction, decay or death.

Additional Reading

1 Bryson, Jo. Effective library and information centres management. Aldershot, England : Grower, 1990.

2. Encyclopedia of management. New Delhi: Crest Publishing House, 1999.

3. Evans, G. Edwards. “Management education for archivists, Information Managers and Librarians: Is there a global core? Education for Information. Vol 2, Dec- 1984, pp 295-307.

4. Katz, Robert “Skills of an effective administrator”. Harvard Business Review. Vol. 52 Sept- Oct., 1974. pp. 90-102.

5. Narayana, G. J. Library and information management. New Delhi: Prentice Hall of India, 1991.

6. Plaunkett , Warren R, and Attner , Raymond F. Introduction to management.

2nd ed. Boston: Kent Pub. House, 1986.

7. Simon, Hebert A. The New science of management. Englewood: Prentice Hall, 1977.

8. Tripathi, P. C. and Reddy, P. N. Principles of management. 2nd ed. New Delhi: Tata McGraw- Hill 1991.