The proxy problem in hiring

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Luke Shipley
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The problem is that in 2020 we still have no idea how well a candidate’s performed in previous jobs. Since we have no way to tell if we’re looking at a top performer or not, we overuse proxies to poor effect. I know this because I got paid to do this for a number of years as a technical recruiter and I carried on doing this when hiring into my own team. But one of the worst hires that I’ve made, had all the positive proxies on paper... This horror story made me sit up and rethink about over-relying on proxies when hiring.

The belief that we share this archetype of what a ‘good candidate’ looks like is some of the most widely-held dogma in hiring. As a recruiter, we accept this hiring hierarchy which says if you’ve worked at a FANG company (Facebook, Amazon, Netflix, Google), or top tier university, you’re considered a top tier candidate—fit for any business. If you’ve worked at a business which has raised a lot of money, or is simply a known brand, or you have a fancy degree, you’re considered a middle-class candidate. For the rest of us mere mortals, regardless of whether you’ve been a top performer, we’re scraping in the mud as lower-class candidates—which is where my CV would sit. This is something which I call the proxy problem in hiring, in which we over-index on proxies which may or may not be relevant. This blog provides some hints for catching your own proxy bias and recognising if it’s genuine, or a false positive.

Disclaimer, I have to be open about my biases. I’ve not achieved any of the feats that will secure top-tier candidate status. I’ve not put in the work to get to a top tier university, let alone complete a degree.

Friends that have put in the work to get into top universities/companies are smart people that worked really hard and deserve the privilege that those achievements bring. I take nothing away from that. It is really hard to get a job at a FANG company so these proxies are a good signal. A job at a top tier company is a great indicator that a candidate has the smarts to pass a tricky interview process. But they are not absolute. Where I’ve run into trouble is with the overuse of these proxies and this learnt behaviour colouring my judgement across the tiers. Where this often goes wrong is:

  1. Putting weight on a proxy which is irrelevant to the position you’re hiring for, such as working for a large corporate when hiring at a startup.
  2. In the middle tier, picking candidates based on the brands they’ve worked for, with no knowledge of their hiring standards, regardless of their performance in the role and the fit for your team.
  3. Being blinded by positive proxies and therefore not taking proper due care and skipping diligence in the interview process (this was the cause of my own horror story).

As a talent person, the single biggest proxy that we’re guilty of over-indexing on is company reputation. At the CV review stage we’ll often rank applicants based on the tier of the companies they’ve worked at. I have to admit, I have to catch and stop myself doing this, alongside scanning CVs for other familiar things. We also proxy with:

  1. University: some would argue that in senior or management roles this is a poor proxy. If you work at a research institution or a corporate with levels of bureaucracy this proxy is more relevant to you. However, this proxy generally seems to be
  2. Location: unfortunately there’s a lot of unspoken discrimination here. It was formerly a good qualifying factor, not wanting someone to relocate for your role. But in an increasingly remote world, I challenge you to fight this bias. In London and SF we blindly would assume higher hiring standards in our home cities because they are known quantities.
  3. Age: sadly lots of discrimination here too, heavily linked to generational bias. There’s a lot more documented about this bias as to why older generations are not favoured in some professions and startups.
  4. Years of experience: often those with a large number of years of experience will tell you that there’s no substitute for experience. But years of experience do not map directly to ability. Two reasons for this are that people learn at different speeds and perfectionist traits can take skills to higher levels. It’s easy for me to relate since I hired a talented grad with no experience, who became a better programmer than me in a tenth of the time.

Starting to sound like a diversity hiring pitch? That’s not where I’m going with this, but the research behind building diverse teams is  In fact, it’s the same cognitive biases that cause these proxy shortcuts that lead us to build less diverse teams. By relying on these gut-driven decisions, we get further away from actual ability and fit for the role in hand.

Why does this happen?

This is not some silly habit a few of us shabby recruiters have developed. As humans, we’re hardwired to take shortcuts. Our old brain has been trained to recognise patterns so that we can make decisions fast and not rethink the same problems over and over. This means we’ve trained ourselves to scan CVs quickly so when we see a positive proxy we think “yes!” Our cognitive biases kick in and we take the easier shortcut our old brain wants us to take so that we don’t have to expend energy thinking too deeply. Read ‘’ by Daniel Kahneman for more on this. To combat these shortcuts we need to be organised and thoughtful, we need considered CV criteria, pre-planned interview questions and clear benchmarks to become more data-driven in our hiring processes.

Sometimes as tech talent people we overuse proxies because often we don’t have the skills to properly screen for and replicate work that will be done in a job. But regardless of your position or skill, it’s hard to replicate real work in an interview, it takes preparation and thought.

The information asymmetry and how to overcome it

Because previous work can be one of the best indicators of future performance, over-relying on proxies in CV reviews and interviews goes on. One reason why the company reputation proxy can be particularly misleading is that there is no easy way to find out how well candidates have performed in previous roles. Would you rather hire a top performer from an unknown company or a poor performer at a mid-tier company? The problem is a reputation problem, since we have no way of carrying reputation from one job to the next. There’s an information asymmetry, the candidate and their previous colleagues, know how well they performed—we recruiters do not. Some candidates benefit from this reputation reset and some are crippled by it.

Good interviewing remains the best indicator of future performance. Do this by setting up your interview committee, agreeing criteria and how to validate it. Part of which can be assessing previous job performance, through good questioning. Second is, but it’s a dark art that many have given up on and few have mastered. can recommend some strategies to  to get some clearer data from past colleagues that can validate information gleaned from good interviewing.

When you catch yourself placing too much weight on company reputation, remember that this has no indication on performance. Performance proxies are job tenure—although this is a moderate signal since we’re rubbish at firing this side of the Atlantic—or movement within a company, such as promotion, or working across a variety of projects. Vertical or lateral moves are one of the best proxies for a company investing in someone, but as with all proxies, take these with a pinch of salt.

The proxy problem in hiring.

This topic weighs heavy on my mind when hearing about employers receiving hundreds of applicants for jobs. The market has quickly turned to an employers market, which I fear will feed into the hocus pocus of proxies getting worse. If you’re hiring, be conscious of overusing proxies and be show care for the crowded job market out there.

This post was written in collaboration with (

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