In this coursework I will be looking at various lines of enquiry based on data collected from Mayfield High School. Therefore I will be doing an investigation into the relationship between height, weight, body mass index and age of boys and girls at this school.
People’s height and weight are affected by their age and gender.
I assume that in year 7-9, more girls would be taller than boys. This is because girls tend to grow faster than boys at the early stages of development but boys eventually grow taller than them. Therefore in year 10-11, more boys would be taller than girls. This also applies to the adults aged 20 and above.
As for the weight, boys are generally heavier than girl. This has to do with their body structure. Therefore I predict that my results will produce a pattern which shows that boys weight more than girls. This pattern will be produced for all age groups: 7-9, 10-11 and 20+. The scatter diagram will have no correlation between age and BMI. This is because the data being used is non-continuous as age group 17-19 has been skipped in this investigation.
The histogram for year group 7-11 will show that most of the students will be underweight but more girls would be overweight than boys. As for the adults aged 20 and above, most of them will be overweight.
There are 1183 students in Mayfield but I need to sample only 60 students. The population has been divided into strata according to their year group and gender too. Therefore I will use the stratified sampling method to randomly select in order to eliminate bias and at the same time ensure that the sample some is proportional to the size of the group in population as a whole. In most cases, the figures will be rounded up or down to the nearest integer.
Boys = 151 x 60 = 7.6 ''' 8 Girls = 131 x 60 = 6.6 ''' 7
Boys = 145 x 60 = 7.3 ''' 7 Girls = 125 x 60 = 6.3 ''' 6