PhD Study : Query Performance prediction in information retrieval

Summary

Query performance prediction refers to inferring retrieval performance of a given query with a search engine. It is useful in a few different ways. For example, if a given query has poor performance, then the search engine may give the user an alert. Thus the initial query can be modified for better performance. It is also possible that the search engine may modify a query automatically. Poor performance to certain type of queries also indicates that there are not enough relevant documents in the corpus and more relevant documents to these queries should be replenished.

Query performance prediction methods can be classified into three categories: post-retrieval prediction, pre-retrieval prediction, and combination methods. Post-retrieval prediction happens when the retrieval results are obtained. It involves the use of contents, relevance scores, and many other features of retrieved results. Pre-retrieval performance prediction uses the descriptive features (such as linguistic features and part-of-speech tags) of query terms, corpus related statistics, and others to predict query performance.

The prediction process happens before the retrieval process takes place, and retrieval results are not required. The third category is combination methods which combine different prediction methods or features into one. Recently, some machine learning methods such as neural networks have also been used in many information retrieval tasks including query performance prediction. The major task is to set up a beneficial prediction model.

A related issue is how to select a group of most useful features from a large number of them. For both post-retrieval prediction and pre-retrieval prediction, dozens of features can be collected.

To undertake this project, it is desirable to have good knowledge on information retrieval, machine learning, and statistical analysis.

Essential criteria

Applicants should hold, or expect to obtain, a First or Upper Second Class Honours Degree in a subject relevant to the proposed area of study.

We may also consider applications from those who hold equivalent qualifications, for example, a Lower Second Class Honours Degree plus a Master’s Degree with Distinction.

In exceptional circumstances, the University may consider a portfolio of evidence from applicants who have appropriate professional experience which is equivalent to the learning outcomes of an Honours degree in lieu of academic qualifications.

Funding and eligibility

The University offers the following levels of support:

Vice Chancellors Research Studentship (VCRS)

The following scholarship options are available to applicants worldwide:

• Full Award: (full-time tuition fees + £19,000 (tbc))
• Part Award: (full-time tuition fees + £9,500)
• Fees Only Award: (full-time tuition fees)

These scholarships will cover full-time PhD tuition fees for three years (subject to satisfactory academic performance) and will provide a £900 per annum research training support grant (RTSG) to help support the PhD researcher.

Applicants who already hold a doctoral degree or who have been registered on a programme of research leading to the award of a doctoral degree on a full-time basis for more than one year (or part-time equivalent) are NOT eligible to apply for an award.

Please note: you will automatically be entered into the competition for the Full Award, unless you state otherwise in your application.

Department for the Economy (DFE)

The scholarship will cover tuition fees at the Home rate and a maintenance allowance of £19,000 (tbc) per annum for three years (subject to satisfactory academic performance).

This scholarship also comes with £900 per annum for three years as a research training support grant (RTSG) allocation to help support the PhD researcher.

• Candidates with pre-settled or settled status under the EU Settlement Scheme, who also satisfy a three year residency requirement in the UK prior to the start of the course for which a Studentship is held MAY receive a Studentship covering fees and maintenance.
• Republic of Ireland (ROI) nationals who satisfy three years’ residency in the UK prior to the start of the course MAY receive a Studentship covering fees and maintenance (ROI nationals don’t need to have pre-settled or settled status under the EU Settlement Scheme to qualify).
• Other non-ROI EU applicants are ‘International’ are not eligible for this source of funding.
• Applicants who already hold a doctoral degree or who have been registered on a programme of research leading to the award of a doctoral degree on a full-time basis for more than one year (or part-time equivalent) are NOT eligible to apply for an award.

Due consideration should be given to financing your studies. Further information on cost of living