You have reached the time when you are about to prepare and write your doctoral dissertation. This piece of work will be the most important of your educational life and is a milestone in an academic career; however it is a daunting task for the uninitiated and is totally different from anything else you have attempted.

Those who struggle with their dissertation usually fail to understand the importance of it, or to fully understand what is required. Dissertation is the bridge which will see you move from graduate to academic, and as such it is the most important piece in the educational system. Many students fall short at this stage in their academic lives because they are simply unprepared for what lies ahead in their dissertation. There are countless classic mistakes that are made that with a little knowledge could be avoided.

And now here you are, attempting a dissertation in Computer Science. To give you the best chance of producing a high quality dissertation read this guide full of hints and tips.

Part 1: About Dissertations

What is a Dissertation?

A dissertation is your final piece of submitted work in a graduate PhD program. It is a detailed and drawn out report that gives credence to a particular hypothesis or research idea. Original thought processes are encouraged in dissertations with the writer usually needing to back up their own findings with scientific and recordable means. It must be a well researched formal piece that at least attempts to offer something new in the sphere of the field in which it is written.

A dissertation is not a collection of facts, but instead is a delving in to the nature of the facts and challenging their validity where applicable. This is achieved by starting with a topic and then researching evidence that will either support the hypothesis or debunk it, this means that a lot of pre planning must go in to a doctoral dissertation and then all the gathered evidence put together in a coherent and readable document. A dissertation differs from a traditional essay in that it does not seek to corroborate published facts or agree with them. Instead it uses them as a basis for debate and as such any statement that is presented as a truism in a dissertation must either be backed by references or must be an original piece of thinking.

Dissertations follow specific set rules in the way they are to be written and structured, with grammatical integrity being considered extremely important. Only formal writing is ever permitted in a dissertation (see below) and no padding is allowed. This means that paragraphs can not be drawn out by fanciful writing because each statement must link to the next in clear prose that only seeks to further an argument or point.

While good writing in a dissertation is important it is not the point of the exercise. Clear theories and evidence to back them up are requirements, and the ability to create knew thought processes within a subject, to offer real debate to your hypothesis. Good writing is essential if you have those things, but if you do not it can badly expose the flaws in your dissertation.

What is the Purpose of a Dissertation?

  1. A dissertation is the student's gateway into an academic career, and so it prepares the student for that world. In the academic arena collaboration is vital and scientists often exchange debates and ideas about their chosen fields. A dissertation will prepare you to be able to communicate efficiently and knowledgeably with fellow scientists.
  2. This knowledge will enable you to create arguments and debates, and to hypothesise theories, while it will also provide tools for deep and clear thinking, and an analytical approach to your chosen field. It should give the student technical know how in their subject as well as the ability to enter and arrange discussions on topics within that subject.
  3. Your dissertation will be something that you will carry with you throughout your academic career. Many scientists hone their dissertations over the years and make it their life's work. Most people choose a topic close to their hearts and become specialists in the same field, making your dissertation a scientific document that could shape your whole career or life.

Part 2: Writing

Uses of Language that are Unacceptable in a Dissertation

A dissertation needs to be a formal and scientific document, and it has no place for words that may seem to be slang, colloquial, jokes or puns. When editing your drafts try to imagine if your writing style would fit into a scientific journal, and what words you never see in such a piece. Any offenders should be removed.

Judging something in a scientific document needs to be handled with care, and avoidance of all humanised moral judgments should be avoided. If you want to comment on the validity of something then terms such as "correct" or "incorrect" are appropriate. However avoid using such terms as "good&", "bad", "awful", or "wonderful". A dissertation should be precise in the things it says and in the statements it makes. There are many words that fall into the bracket of judgments and while avoidance of all of them all of the time may be taxing, it is well worth it come the end of the project. The sentence "this theory is perfect" holds little water because it is your judgment and nothing is perfect, however "this theory is correct" is acceptable.

"I found this case to be most perplexing." If you were reading that sentence as part of a paper in a published journal, what would be wrong? It is the "I", when writing your dissertation try to avoid using terms that signify you, or a team, or the use of the word we. Simply because the story telling aspect of these words does not fit into a serious scientific paper, and it is of little to no relevance (remember each statement must have relevance). Other words that also bring an unwanted personal touch are "seems" and "appears", all that matters are the facts, not how things seem. This excessive personal touch can be carried to talking in the first and second person, so avoid phrases such as "I locked the cage", or "You will see how the cage was locked".

Everything you put into your dissertation should be measurable and quantifiable. Colloquial terms such as "kind of", "lots of", "something like", and "just about" are too vague and mean nothing in terms of research and debate. See below for two examples.

"There were lots of water droplets on the net." How much is lots of? If an experiment has been carried out then there should be a precise reading.

"There were 10,000 water droplets on the net." Of course this is correct because it actually states an amount that can be measured.

"The world is probably black, and is obviously square." This wholly ridiculous statement only really has two wrong words in it because probably and obviously cannot be used accurately in a scientific paper. Probably is extremely vague and sounds as if not enough research on the topic has been done, while it is also a fallacy to say that something is probably the case, because it cannot be measured for accuracy. Of course this is because what is obvious to one person may be totally different to another.

Also try to steer away from words that may come across as a declaration of proof.

"It always rains in Tucson." Nothing is definitive; even if you have experimented and researched you cannot say something always occurs, so try to avoid the word "always".

"It must be red that comes out next." Again, why must it be?

"The last ball should have been 14." Who says that it should be?

These words only put the burden of proof on you, the writer. Unless you are an eminent expert in your field it is unlikely that you can prove anything, so it is best to avoid such words.

All the above words should not be used, but there are times when they are unavoidable, especially as many are common linking names, but it is this avoidance of colloquial terms that should be practised.

Using Terms

Technical terms within dissertations can be hard to understand, and many students end up falling into the same mistakes. A simple rule is to follow definitions as they have been published before in other places, and be sure to make reference of this. A term should only be used in one way once it has been used once; this avoids the confusion of something with the same meaning popping up all over your document but in different guises.

A quick fix to having to explain your used definitions each time is to include a statement about the definitions used in your dissertation. Reference the style of definition, and where you got it from.

Use of Constructions

Use of passive construction sentences is typically frowned upon in dissertations, and active constructions are preferred. A passive sentence is when the subject is the receiver of the action, and active is where the subject is the doer of the action.


To make your writing stronger and more easily read from an academic viewpoint present tense sentences are advised. Past tense brings in a story telling aspect to the writing that is unnecessary in academic papers and makes the validity of the point weaker.

Avoid Talking About People and Storytelling

Many students make the mistake of believing that if they make their dissertation a snappy piece of writing that it will gain them more marks. Remember you are not trying to tell a story, you are attempting to make a profound scientific point. There is no need and no place for drama, indulgent humour, or false tension.

"The breakthrough came when we realised the power was off." This kind of sentence is completely inappropriate in a dissertation because we do not need to know something immeasurable and unimportant to the final result. Also do not under any circumstances use names of either yourself or a colleague or helper, this is over personalizing your dissertation and is irrelevant to the overall goal. There is little need to document the events leading up to a result or experiment, only the final outcome and analysis are important.

Another trap in the storytelling mistake is that students use statements that suggest an outside force created some luck. "Over the 7 days we attempted the experiment, it only worked at noon each day," this implies that some force was at work and the actual outcome was blind luck. Of course this would never be the case and your dissertation should be a completely factual piece that bases all of its statements in truisms. Most students write in this manner without ever noticing, but your dissertation will be a much better scientific log without this storytelling.

Talking about your self can also take on a vaguer disguise. While you may succeed in not talking about yourself outwardly, you should also be wary of praising a particular experiment or finding, or equally of being critical of another.

Separating Concept and Instance

An instance of a concept happening is not the same as the concept itself. If that seems difficult to grasp then that is because it is, and many students make the mistake. A simple example would be that a concept occurs with an algorithm, the algorithm is the concept, but the program that runs the algorithm creates the instance of the concept but is not actually the concept.

There is a similar problem when it comes to separating knowledge and data, and again many students fail to see the difference between the two. Data is something that has been gleaned from an experiment or series of experiments, while knowledge is acquired when the data has been analysed, understood, compared against other experiments and then converted to something tangible.

Master Cause and Effect

Dissertations need to be able to analyse data and find conclusions from it. This means it needs to be able to know the differences between what causes something and what it affects. Mastery of this can give the student deep insight into their topic and can allow them to delve deeper into the thought process. To determine what can be attributed to cause and affect the student must be efficient in analysing findings and eliminating any outside influences or non logical ones.

Coming to the Right Conclusions

When writing your dissertation you must be vigilant and make sure that you come to conclusions that actually have merit. This can be achieved by only using hard evidence to back up conclusions you have drawn, while use of speculation merely adds another variable and avoids an answer. For example if computer A takes 5 minutes to start up and computer B takes 2 minutes, this cannot definitively be attributed to one having a quicker start up processor. Not unless every possible variable within the machines have been checked and eliminated as causes.

Do not Seek Fame or Political Notoriety

Even though you may have struck upon a world changing idea you should never through the course of your dissertation mention it as a marketable entity. Independence from the commercial viability of an idea is important as scientists are only in search of an answer and not money or fame. Even if the idea is commercially exciting, this should not be the reason for the findings or the merit of them, so statements like "Program X could be in 400 million machines within a year," are unnecessary in a dissertation.

Likewise as a scientist you should avoid any political sway that your findings may hold. You are writing a dissertation based on scientific findings and are not being an activist. You should be looking to act independently of any state or political group.

Part 3: Arranging Your Dissertation

Every dissertation starts with a problem, and as the student you will need to explain why you have chosen that problem, why it needs to be solved, why it is worthy of attention, what new ideas you can add to the existing thoughts already published, and find validity for your ideas in a strong conclusion. Before planning your dissertation in Computer Sciences, take a look at this basic structure for some tips on how best to arrange your dissertation.


A discussion of the topic and problem that you have chosen to look at, and what works there are already published. What will you add in your in depth look at this problem and what particular theories and ideas you have and will be addressing.

Conceptual Model

Your dissertation should be much more than a collection of ideas, and instead should be an organic and flowing document that follows a theme and moves from chapter to chapter in cohesion. This is where you can discuss the concept of your dissertation and what you will be answering throughout the paper, although this will be a brief conceptual summary before the in-depth analyses throughout.


You have put across your hypothesis, and now you are going to have to back it up with evidence. This is where you detail the experiments and research programs you undertook to achieve your results and how you managed the data and interpreted it. You will also need to produce findings that help to promote your ideas and conclusions. If your hypothesis was well researched and is valid the experiments should corroborate what you predicted in the earlier parts of your dissertation. This category can be split into two chapters if it suits the individual, the first an in-depth look at the experiments and the second a break down of the results and what they mean.


You have shown through your experiments that your theories on your chosen subject can be applied. Now you need to summarize what future studies or developments need to be undertaken to continue your research.


Here you can offer a brief summary of your dissertation and include any contributions you had. This is also the place to discuss problems faced and how they were overcome.

Part 4: Summary

Even though a dissertation in Computer Science can be extremely taxing on your resources and mental faculties, following these tips can make it an easier experience. This is possibly the most important scientific document you will ever write, and it is your first! It may not carry the weight or importance of your future endeavours, but it is the one that provides that vital stepping stone to the next stage of your academic career.

Plan your dissertation meticulously, and always seek advice from hand outs such as this. Make sure you follow the style guides and use the best and most valid information you can find, and most of all make sure that you enjoy the experience and produce your best work.