Statistics, lightly

Median, outliers and reading a price spread

Updated October 2, 2026 4 min read

The median sold price is the middle value of your sorted sold comps, and it is the number to price from because one odd sale barely moves it. In a set of 11 sales, ten between $40 and $55 and one at $400, the median is $47 and the average is $79. The average sits above every sale except the $400 one.

Pricing does not need statistics, but it needs three of its ideas. Each one takes a minute to understand and prevents a specific expensive mistake.

Why use the median instead of the average for pricing?

The median is barely affected by extreme values, while the average is pulled hard by them. Sort your comps and take the middle value. That is the median. It answers the question you have, which is 'what does this typically sell for'.

In a set of eleven sales, ten between $40 and $55 and one at $400, the average is $79 and the median is $47. The $79 is arithmetically correct and higher than every sale except the $400 one.

The median hardly notices the outlier. That stability is what you want from a pricing summary. eBay's price guide for sports cards lists the median sold price too, per eBay's pricing help page.

What should you do with outlier sold prices?

Open them before you delete them, because an outlier can be a fact about a listing rather than an error.

• A high outlier may be a rare variant, a bundle, exceptional photographs, or a bidding war. If it is a variant, check whether yours is that variant. That is a considerably more valuable finding than a median.
• A low outlier may be damage, missing parts, a poorly written listing, or a seller who needed a fast sale. If it is a bad listing, it tells you there is room above the median for a good one.

Open the highest and lowest comp before trusting either. It is a quick check, and it explains an outlier instead of just flagging it.

What does a wide spread in sold prices mean?

A wide spread in your sold prices means presentation, condition or variant is driving price, and a very wide spread means your comp set is probably mixed. The width of the middle of your data matters as much as its center. A useful way to read it is the range covering the middle half of your comps, ignoring the top and bottom quarters.

How do you apply this to your own sold comps?

Sort the list, look at the middle, open the ends, notice the width. That is the whole discipline. The comp analyzer does the sorting and flags the outliers so you can go straight to reading them.

How many sold comps do you need?

Enough that one unusual sale cannot move your answer much. A rule of thumb: eight is a working minimum, fifteen is comfortable, and beyond about twenty you may be adding older and less relevant sales rather than improving accuracy.

Below eight, treat the number as provisional and be more willing to adjust it after the market responds. That is the thin-comp situation.

Keep reading

• When to lower your price on eBay, and by how much

  A schedule that avoids both panic discounting and listings that sit forever.

• How to price an item with no sold comps

  Proxy comps, floors, the descending-price method, and when to walk away.