figure - sample data points from the wine quality dataset the output depicted in figure - shows us sample wine records for our wine quality dataset looking at the valueswe can get an idea of numeric as well as categorical features let' now try to gain some domain knowledge about wine and its attributes domain knowledge is essential and always recommendedespecially if you are trying to analyze and model data from diverse domains wine is an alcoholic beverage made by the process of fermentation of grapeswithout the addition of sugarsacidsenzymeswateror other nutrients red and white wine are two variants usuallyred wine is made from dark red and black grapes the color ranges from various shades of redbrownand violet this is produced with whole grapesincluding the skinwhich adds to the color and flavor of red wines giving it rich flavor white wine is made from white grapes with no skins or seeds the color is usually straw-yellowyellow-greenor yellow-gold most white wines have light and fruity flavor as compared to richer red wines let' now dive into details for each feature in the dataset credits once again go to karlijn for some of the attribute descriptions our dataset has total of attributes and they are described as follows fixed acidityacids are one of the fundamental properties of wine and contribute greatly to the taste of the wine reducing acids significantly might lead to wines tasting flat fixed acids include tartaricmaliccitricand succinic acidswhich are found in grapes (except succinicthis variable is usually expressed in tartaricacid in the dataset dm volatile aciditythese acids are to be distilled out from the wine before completing the production process it is primarily constituted of acetic acidthough other acids like lacticformicand butyric acids might also be present excess of volatile acids are undesirable and lead to unpleasant flavor in the united statesthe legal limits of volatile acidity are / for red table wine and / for white table wine the volatile acidity is expressed in aceticacid in the dataset dm citric acidthis is one of the fixed acids that gives wine its freshness usually most of it is consumed during the fermentation process and sometimes it is added separately to give the wine more freshness it' usually expressed in in the dm dataset residual sugarthis typically refers to the natural sugar from grapes that remains after the fermentation process stopsor is stopped it' usually expressed in dm in the dataset