STA10001 Chapter Notes - Chapter 1-2: Bar Chart, Categorical Variable, Descriptive Statistics
Document Summary
Variable anything we want to measure. Categorical variables that we classify by putting into groups nominal number used to symbolize a category/group ex. Need to define the category as a particular number. Ordinal numbers have additional meaning - order. Metric variables we can measure or count reasonably accurately. Interval and ratio referred to as scale on spss. Interval fixed numbers same interval between each possible number value. Ratio weight, no of people in a class. Some variables can be measured either on metric or categorical basis. Look at what a variable represents, includes missing values, measurement type (pg 223 frequency tables, bar charts, pie charts) missing values some people may not choose to reply, answer. Valid total the items we were able to get information from. Work out data from total less missing values but acknowledge missing values. If less than 3 or 4, pie charts. When there are more than categories, pie charts are not useful too cluttered.
