Well, kreynolds is right. An average fighter vs. an average rogue, the fighter decimates the rogue every time. Let's take two examples- in each we'll assume that the rogue tries to bluff the fighter, then attacks, etc.
Level 1:
Fighter stats: 15 13 14 10 12 8 (iconic fighter), equipment Scale Mail, Large Shield, Longsword, AC 17, Feats Weapon Focus, Improved Initiative, Power Attack.
Atk +3, damage d8+2. Hps 12.
Rogue stats: 12 15 10 14 8 13 (putting 13 in charisma to aid bluffing potential, otherwise iconic rogue). Equipment: Rapier, Studded Leather, AC 16 (including Dodge). Atk +1, damage d6+1; Feats: Improved Initiative, Dodge. Rogue has 6hps.
Round 1: Assume rogue wins initiative. Attack fighter, chance to hit=30%, average damage on hit (2d6+1) =8. Therefore, average damage is 2.4. FIghter has 9.6 hps remaining
Fighter attacks next. Chance to hit= 45%, average damage on hit is (d8+2)=6.5. Average damage is just over 2.5. Therefore, even when the rogue is sneak attacking, fighter does more damage AND since rogue has fewer hps, rogue will invariably lose (his going first reduces the fighter to 9.6, still commensurately more than his mere 6). NB The rogue has the same average chance to get a critical- his threat range is larger, but his confirmation range is smaller, so it balances out.
Level 10:
Fighter stats: 17(19) 13 14 10 12 8, equipment +2 Full-Plate, +2 Amulet of NA, +2 Ring of Protection, +2 Longsword, +2 Large Shield. AC 28. Feats: Weapon Focus, Weapon Spec, Improved Crit, Improved Initiative, Power Attack, Cleave, Great Cleave, Expert Tactician, Combat Reflexes, Hold the Line, Death Blow. Atk +17/+12, damage d8+8 (average 12.5). HPs 80.5.
Rogue stats: 12 17(19) 10 14 8 13, equipment +2 Mithral Chain Shirt, +2 Amulet of NA, +2 Ring of Protection, +2 Rapier, +2 Mithral Buckler. AC 28 (including Dodge). Feats: Improved Initiative, Dodge, Mobility, Spring Attack, Quicker than the Eye. Atk +10/+5, damage d6+3 (average 6.5, or 23 if sneak attacking). HPs 38
Round 1: Assume rogue wins initiative. Attacks flat-footed fighter, chance to hit=20%, average damage on hit is 23, therefore average damage is 4.6. Fighter then uses full-attack, chances to hit= 50%, 25%, average damge on hit=12.5. Therefore, average damage is around 8.5 (more than the rogue by quite a margin). The rogue has now the option of bluffing as an MEA (QttE) and then attacking, in which case he will lose (fighter does more average damage AND has more HPs) or spring attacking (can more further). However, this doesn't help. His average damage dealt drops to 20% of 6.5, a mere 1.3hps, and the fighter can simply charge him to make up the difference. Ergo, the rogue loses.
I couldn't be bothered to do a top-level example, it would take too long, but these two illustrate the case adequately: a fighter vs. a rogue of equivalent level will win unless the rogue has incredible luck.
