7.6 a Prior to deciding on your quota you will need to consider the possible inclusion of residents who are aged under 16 in your quota. Often in such research projects residents aged under 5 (and those aged 5–15) are excluded. You would need a quota of between 2000 and 5000 residents to obtain a reasonable accuracy. These should be divided proportionally between the groupings as illustrated in the possible quota below: Gender Age group 16–19 20–29 30–44 45–59/64 60/65–74 751 Males 108 169 217 285 110 59 Females 154 209 180 203 205 99 b Data on social class, employment status, socioeconomic status or car ownership could also be used as further quotas. These data are available from the Census and are likely to affect shopping habits. c Interviewers might choose respondents who were easily accessible or appeared willing to answer the questions. In addition, they might fill in their quota incorrectly or make up the data.