Constituency: constituency candidate is running in (e.g. “Aberavon”, or “York Central”)

Region: region constituency is in (e.g. “Wales”, “West Midlands” or “Yorkshire & Humber”)

Country: country constituency is in (i.e. England, Northern Ireland, Scotland, Wales)

Current holder: party that held constituency seat at time of dissolution of parliament (May 3, 2017).

Margin: Margin by which the current holder won seat the last time it was contested (generally the 2015 General Election, or otherwise the most recent by-election).

Full name: Full name of the candidate, as released by respective party.

Party: Party the candidate is running for (i.e. Labour or Plaid Cymru).

Sitting MP: Whether or not a candidate was a member of Parliament by the time of the dissolution of Parliament.

MP Since: The year a candidate became a member of parliament.

Gap in term: In some cases, MPs did not serve all years since first entering parliament. Those years are marked (e.g. did not serve between 2010-2012).

Date of Birth: Date of birth of candidate. When only the year is available, DoB are listed as January 1st (e.g. 1-1-1973).

Place of Birth: City or town of birth of candidate, or the wider area if more detailed information is unavailable.

Gender: Gender of candidate. This is often based on limited information available in the public domain. We apologise for any mistakes and encourage you to get in touch if this information is incorrect (or no longer correct).

Secondary School: Last secondary school a candidate attended (e.g. Eton College). In some cases schools may have changed names since.

University undergraduate degree: University where candidate completed undergraduate degree (e.g. University of Leicester). In some cases, colleges within universities are also listed (e.g. University of Oxford- Magdalen College). Candidates that did not attend university are listed as “None”, and as “NA” when information was not available.

Field undergraduate degree: Degree field undergraduate degree- exact names have been copied over (e.g law, Spanish or PPE). Candidates that did not attend university are listed as “None”, and as “NA” when information was not available.

STEM Undergraduate Degree: Lists whether a candidate’s undergraduate degree is a STEM-degree, based on the official HASE definition.

University postgraduate degree: University where candidate completed post-graduate degree (e.g. University of Leicester). In some cases, colleges within universities are also listed (e.g. University of Oxford- Magdalen College). Candidates that did not complete a postgraduate degree are listed as “None”, and as “NA” when information was not available.

Field postgraduate degree: Degree field graduate degree- exact names have been copied over (e.g law, Spanish or PPE). We do not list the type of post-graduate degree (e.g. PhD, MSc, etc.) as these were unavailable in too many cases. Candidates that did not complete a postgraduate degree are listed as “None”, and as “NA” when information was not available.

STEM Post-graduate Degree: Lists whether a candidate’s undergraduate degree is a STEM-degree, based on the official HASE definition.

Degree category: We have manually classified each candidate’s degrees within a smaller set of categories, using the following rules:

* Preference is given to postgraduate degrees over undergraduate degrees (e.g., a PPE undergraduate and law graduate will be categorised as “law”).

* If a candidate completed similar-level degrees in multiple fields (e.g. Philosophy and Mathematics), both fields are listed in the degree category field, separated by a comma.

Because of the preference given to postgraduate degrees, some predominantly undergraduate fields (such as PPE) would be undercounted when aggregating by degree category alone. When such as statistics are of interest, we advise using the undergraduate and postgraduate columns instead.

Merged STEM: If either a candidate’s undergraduate of postgraduate degree is in a STEM field (or both), this field is marked “Yes”, and a candidate is considered a STEM-candidate for our analysis.

Current or last job: This field lists a candidate’s current job (when not currently a member of parliament) or last job before joining parliament. This field has not been standardised (similar jobs may be listed under a variety of different names). When a candidate has had a long career with many different previous jobs, the most recent was selected.

Previously worked in parliament: Marks whether a candidate previously worked in parliament (Westminster, the European Parliament, the Scottish Parliament, etc.) in a non-elected role. Frequent careers include assistant to a member of parliament or special adviser. This list is likely underestimating rather than overestimating the number of former parliament-workers, given the paucity of data.