Q. 180  Highlight the advantages of heuristic methods over classical problem solving methods. When should we prefer heuristic methods? 

 

Note for website visitors - Two questions are asked every week on this platform. One on Tuesday and the other on Friday.

• All questions so far can be seen here - https://www.benchmarksixsigma.com/forum/lean-six-sigma-business-excellence-questions/
• Please visit the forum home page at https://www.benchmarksixsigma.com/forum/ to respond to the latest question open till the next Tuesday/ Friday evening as per Indian Standard Time.  
• The best answer is always shown at the top among responses and the author finds honorable mention in our Business Excellence dictionary at https://www.benchmarksixsigma.com/forum/business-excellence-dictionary-glossary/ along with the related term.

 

 

Advantages
Any approach with short timeline for finding a satisfactory solution for a complex problem
Provides immediate goal
Reduces cognitive load

When should we prefer heuristic methods? 
TIme duration is shorter
complex data and decision cannot be taken easily
Identifying intial problem for a complex situation

Heuristic Methods or Heuristics (as it is famously known) is a problem solving approach where one takes a discovery mode to problem solving instead of a well defined and structured (classical) problem solving approach. Such approach may not yield a perfect solution but is usually sufficient in obtaining a good enough solution which works in the short term.

 

You may also refer to heuristics as 'Nani and Dadi ke nuskhe'. They will have a cure for common ailments which might seem illogical, but they still work  It is similar to when you know something works without understanding why it works. 

Therefore, I believe it is a more practical approach to problem solving. Classical problem solving methods can be taught to someone, however, Heuristics cannot be taught. This is something one learns!! Maybe that is the reason, organizations ask for experience and qualifications.

 

Theorists have classified heuristics into multiple types, however the most common ones are 

1. Trial and Error

2. Solve by example or solve by seeing

3. Rule of thumb

4. Intuitive guess work etc.

 

The advantages of Heuristics will be similar to situations in which this approach will be preferred over the classical problem solving methods

 

1. Shortage of Time - consider that you are taking an exam and solving multiple choice questions. The logical approach would be to solve the question and then mark the answer. However, you do not have that much time. The heuristic approach would be 'elimination of options'. The same objective of selecting the correct answer is achieved

 

2. Lack of complete knowledge - literature with higher knowledge is present, but you are unaware of that knowledge

3. Current complete level of knowledge is inadequate - you are the domain expert and you possess all the knowledge that is available in that particular domain, but that current level of understanding is unfit in solving for the problems that we face today. As Einstein quoted - 'Problems cannot be solved by the same level of thinking that created them'.

In both of these scenarios, one adopts the famous method of Trial and Error. For e.g. the objective of the Formula 1 car manufacturer is to increase the straight line speed of the car by also maintaining sufficient downforce. The design team probably has the complete knowledge of the engine and body frame - its make, its components, its design limitations etc. - but still they try a lot of different combinations to meet their objective and that is how new designs come out.

 

4. High level of accuracy of solution is not required. E.g. a company wants to launch a new product. They do not want a highly precise value of the potential market size. They are ok with a guesstimate as well. They may not take a well structured approach in determining the market size. They might end up working with some macro indicators and basis their experience, they will guess the market size

 

5. Structure problem solving is complex - assume you have no shortage of time, you have the complete knowledge about the problem and the solution should also be accurate. However, the problem itself is so complex, that even after applying the structured problem solving methods, you are unable to identify the causes and/or the solutions to the problem. In such situations, you may revert to Heuristics for problem solving. One example could be drug discovery. 

 

The choice between heuristics vs classical problem solving methods always has a risk of a trade off between accuracy of solution and effort put in for solutions. If risk of the failure is not too big or is unknown, heuristics offer a better trade off i.e. you get a better solution with little effort. Finally, you can always put 'Method to Madness' and convert the Heuristic solution to a well defined, logical and structured solution.

Problem Solving: 

 

in today's world, there is very highly complex environment for businesses and a huge competition between each other  to sustain in the market and companies are searching various ways to gain the market by improving their products or services quality, increasing their speed of work, improving efficiency. while achieving these goals companies are facing various problems which can be in-house or in supply chain or problems in searching for a new business/opportunities or any decision making. 

There are basic four principles for solving any problem which are given below:

 

1. First, Thoroughly understand the problem 

2. Second: make a plan to solve this

3. Third: work out on that plan 

4. Fourth:  do evaluation and then adapt it for future 

 

There are various methods to solve any problem and Heuristic Method is one of them. Further we are explaining more about Heuristic Method;

 

Heuristic Method:

 

Heuristic methods are not formal methods but are practical and mathematical approach which is used to find a solution of any problem. While applying these methods we consider Quick Fix to solve any problem and to speed up the solution process we use our previous experience considering that solutions which are developed does not necessarily need to be optimal or perfect solution for the required problem. Previous experience with same kind of problem or same kind of business is also used to take decision but sometimes it may lead to wrong direction also. This can be treated as Quick fix but it can introduce error, bias in the solution.

 

For example, any Fast-food company wants to grow their business in other countries and found that India is a very big market for the same and decided to invest, but after sometime they found that losses are their after initial set-up. Because they took decision on the basis of heuristic method by their experience and intuition. Later on they found that they did not researched properly about the taste of Indian and food of their interest.

 

Heuristic Techniques:  

there are various heuristic techniques used while solving a problem which are given below:

 

1. Dividing Technique or decomposition: break down the main problem into small segment and start attacking on them one by one and combine all solution in the end conditionally all sub problems should be linked to linked to each other.

 

2. Inductive Technique:   in this we refer our previous learning of the same kind of problem 

 

3. Reduction Technique or Limitation:  usually problems deals with different different causes and factors and comes out a big one than considered. in this technique we set our limits for that problem which makes it easier to solve.

 

4. Constructive or serial Technique: in this we approach by step by step and we consider small solution in every step as our victory and then proceed further to catch another one. 

 

5. Multiple Mind Technique: in this we give preference to include other people while solving any problem for their input and use them as available resources. 

 

Advantage of Heuristic Methods over Classical Methods:

 

Heuristic methods have various advantage over classical methods. Some of them are given below:

• these methods are quick fixer and give solution very quickly
• limits the problem solving and focus on immediately doable things.
• these concepts are simple and very efficient to use
• Promotes an individual as a problem solver by focusing on immediately doable.
• can solve a problem very rapidly 
• Achieve immediate goals 
• can speed up the process after finding a satisfactory solution 
• works very well with complex data 
• provides timely solution or decisions
• Provides Practical solutions which are easy to understand and implement
• Provides short-term solutions

Disadvantage of Heuristic Methods:

 

Heuristic methods have many disadvantages with its advantages. Some of them are given below:

• unable to provide a optimal solution
• solutions are for very short-term
• not able to give power to the solution which can be used for long term for greater productivity or any profitability
• have error and bias in the judgement
• Data selection might be insufficient which leads to inaccurate decision

Preference of Heuristic Methods;

 there are various situation where we can prefer Heuristic methods to solve any problem. Some of them are given below:

• The situation where we found that the processing speed is important as much as the final solution, we prefer Heuristic methods.
• Heuristic methods are preferable because they provide good solution very quick and other methods are time consuming to solve any problem.
• where we can go with small term goals and are satisfied with small wins with satisfactory results
• we can prefer heuristic methods where we can use following heuristics:
  • thumb rule
  • any experience or educational guess
  • common sense
  • any intuitive judgement
• Where we want to achieve small goals 
• where we are focusing on immediate doables 
• where we want temporary solution 
• where we aim for only to implement known or readily accessible solutions
• where it is impossible or impractical to find an optimal solution , we prefer heuristic methods
• where we want to increase the speed to find a satisfactory solution

 

Let's have a one example of Heuristic method:  There is lot of 1000 parts produced by a sheet metal department in an automobile industry. Before delivery, during quality check, inspector found that these parts are defective and have thinning in all parts.The concerned department can not hold the parts because it leads to stoppage of Main Line of next department and the department can not reject these defective parts as the part cost is very high.People tried to think about the solution how to deliver these parts and followed heuristic technique of multiple mind with following heuristics:

• Common sense: Someone suggested that this part is of C rank and will not be assemble in critical area in final assembly and have very less importance which is not directly visible also, so we can deliver these parts but still thinning is there.
• Thumb Rule:  Someone else suggested about the thumb rule of 25% thinning which is allowable , they applied the same and checked all parts and found thinning  within 25% and deliver all the parts 

So by following heuristic , they have saved rejection and supplied parts to next department so that there was no loss on main line. So they are satisfied with this solution. later on they can find out the reason of thinning in their process and can take C/M accordingly.

A heuristic method is an approach to finding a solution to a problem. Heuristic methods speed up the process of reaching a satisfactory solution.There are four Principles :

1. Understand the Problem

2.Make a solution.

3. Carry out the plan.

4.Evaluate & Adopt

 

1. Understand the Problem

It can help to draw the problem and to look at it from another angle. What is the problem, what is happening, can the problem be explained in other words, is there enough information available, etc. Such questions can help with the first evaluation of a problem issue.

 

2.Make a Solution

There are many ways to solve problems. This section is about choosing the right strategy that best fits the problem at hand. The reversed ‘working backwards’ can help with this.It can also be useful to make an overview of the possibilities, delete some of them immediately, work with comparisons, or to apply symmetry. Creativity comes into play here and will improve the ability to judge.

 

3.Carry out the plan

Once a strategy has been chosen, the plan can quickly be implemented. However, it is important to pay attention to time and be patient, because the solution will not simply appear. If the plan doesn’t go anywhere, the advice is to throw it overboard and find a new way.

 

4.Evaluate & Adopt 

Take the time to carefully consider and reflect upon the work that’s already been done. The things that are going well should be maintained, those leading to a lesser solution, should be adjusted. Some things simply work, while others simply don’t.

 

Heuristic methods are Non conventional method of conducting the problem solving exercise, wherein we get to know the best optimized solution of the problem, for which the solution through statistical approach is either not possible or not feasible. This is very useful in cased where in the general problem solving technique is unable to get to the root cause and validated countermeasures.

Heuristic methods employ various tools and techniques, processes and procedures to come to the best agreed optimized solution.

 

Some of the Heuristic tools include Trial and error, Best among many, Experience level, Satisfactory level, Prioritization, Behavioral aspects etc. These tools can be applied when the circumstances where we are not able to get the commonly agreed solution to the problem through logical approach. some of the examples may include"

 

1. Financial Investment : To decide on the scope and direction of equity and non equity investments in particular financial domain

2. To finalize the location of land among few option for starting of a new industrial venture

3. To identify the area of hot spot customers which requires to be focused when the statistical  data is misleading.

 

To conclude, Statistical and systematic approach to problem solving is praiseworthy and must be employed but an organisation must deploy the heuristic methods based on need and applicability. For this to happen there should definitely be the reserve of knowledge, skills, expert panels, experiential data etc.

The chosen best answers are that of Manjula (for examples) and Vastupal (for the detail). Read through Natwar's answer for additional insights.