The phrase "a perceived increase in" is correct and usable in written English.
It can be used when discussing an increase that is recognized or believed to exist, even if it may not be objectively measurable.
Example: "There has been a perceived increase in customer satisfaction since the new policy was implemented."
Alternatives: "an observed rise in" or "a noticeable growth in".
In the present study we show that a visual illusion, which induces a perceived increase in a step's riser height, results in increased safety during subsequent step negotiation because of an accompanying increase in toe elevation.
The MCC is set to launch a trial with club, university and schools cricket in 2017 to eradicate a perceived increase in excessive sledging and violent behaviour.
Twenty years ago, when I was working at the House of Commons, a perceived increase in threat led to an enormous ratcheting up of security throughout the building.
Several parliamentarians blamed a host of cultural factors for a perceived increase in sex crimes, from the influence of Western culture to television advertisements for condoms and provocative films.
Bakiyev faced emerging criticism on a number of key issues, however, including a perceived increase in corruption, which had been a central factor leading to the demonstrations against the government he had been elected to replace.
Thirty-seven students (57.8%) reported a perceived increase in knowledge after the activity.
The decision to significantly expand the infrastructure for monitoring political campaigners was taken in the late 1990s, amid an perceived increase in activity by animal rights and environmental campaigners.
Increased production of MCP-1 and MMP-1 might increase the chances of detecting positive cells, which could result in a perceived increased in the number of cells expressing these factors (a threshold effect).
First, to a large fast-moving-consumer-goods manufacturer with huge sales in environmentally conscious western Europe, a small increase in costs can be easily offset by a large (perceived) increase in revenues.
From their perspective, such measures could become more problematic due to a perceived increase of conflicting land use claims in the urban region.
A large fraction of farmers perceived increases in annual rainfall despite instrumental records indicating no significant trends, a finding that may be related to greater perceived water availability associated with irrigation growth.
