Online broker E-Trade recently released the results of its quarterly pulse check on experienced investors. The report found that nearly a quarter had made early withdrawals from a retirement account — and of those, roughly half under age 55 regret it. The reason might be because they’re uneducated when it comes to investing basics. About half of those surveyed said they wished they’d taken a course in saving for retirement or understanding the markets when they were younger, indicating that even seasoned investors could benefit from more training.