Expected Value Formula:
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Expected Value is a fundamental concept in probability theory that represents the average outcome of a random variable over many trials. For loot boxes, it calculates the average return per box opened.
The calculator uses the expected value formula:
Where:
Explanation: The formula multiplies each item's value by its probability of appearing, then sums all these products to get the average expected return.
Details: Calculating expected value helps consumers make informed decisions about purchasing loot boxes, understanding the average return on investment, and evaluating whether the potential rewards justify the cost.
Tips: Enter the number of items in your loot box, then for each item provide its value (in any currency) and probability (as a decimal between 0-1). Ensure probabilities sum to 1 for accurate results.
Q1: What if my probabilities don't sum to 1?
A: The calculator will still work, but the result may not accurately represent the true expected value. For precise calculations, ensure all probabilities sum to exactly 1.
Q2: Can I use percentages instead of decimals?
A: No, the calculator requires probabilities as decimals (e.g., 0.25 for 25%). Convert percentages by dividing by 100.
Q3: What currency should I use?
A: You can use any currency unit (dollars, euros, coins, etc.) as long as you're consistent for all item values.
Q4: How accurate is the expected value?
A: Expected value represents the theoretical average over infinite trials. Actual results may vary significantly in the short term due to randomness.
Q5: Should I always choose loot boxes with higher expected value?
A: While higher expected value generally indicates better average returns, consider other factors like risk tolerance, item utility, and personal preferences.