Guess
Speculation
A recollection and measurement of the situation is what I use to make a guess and speculation.
おくそく
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
人々は、その試合は八百長だったのではないかと憶測している。
People are speculating that the match may have been fixed.