TY - JOUR T1 - Effect of Denoising Autoencoder in the view of Item Popularity Bias AU - Kim, Jinhong AU - Lee, Jae-woong AU - Lee, Jongwuk JO - Journal of KIISE, JOK PY - 2021 DA - 2021/1/14 DO - 10.5626/JOK.2021.48.5.575 KW - denoising autoencoder KW - collaborative filtering KW - top-N recommendation KW - item popularity AB - Denoising autoencoder (DAE) is commonly used in recent recommendation systems. It is a type of Autoencoder that trains by giving noise to the input and has shown improved performance compared to autoencoder. In this paper, we analyze the effect of noise in terms of item popularity to interpret the training of DAE. For analysis, we design the experiment in the following two ways. First, we observe the changes of the learned item vector’s L2-norm by giving noise to the autoencoder. Second, by giving noise only to presampled items by popularity, we anlayze whether the improved performance of the DAE is related to item popularity. Results of the experiment showed that the variance of the item vector norm caused by popularity was reduced by noise, and that the accuracy increased when noise was given to the popular items.