1 Record or upload your video. 2  At the end of the video processing stage in the upload interface, you will see an option to choose a Custom thumbnail under the Video thumbnails section. 3  Go to your channel Video Manager. 4  Locate a video and click the Edit button. 5  Click the Custom thumbnail button and upload a thumbnail.
Median is the middle number of a given dataset (if itÃÂ­s odd) while average is a definition of arithmetic mean, which is the most oft-cited average. The value of median depends on the number of elements in a data set (odd or even) while average does not.
Using median, rather than mean income, results in a much more accurate picture of the average income of the middle class since the data will not be skewed by gains and abnormalities in the extreme ends.