The Relationship between Height and Weight in Mayfield High School
The hypotheses that I have made are effective but simple. I expect to
1) Boys weigh more than girls
2) Girls are taller than boys in KS3
3) When I investigate the relationship between height and weight, I
expect to find that
the taller you are, the heavier you weigh.
4) Gender may affect the results that I will have attained by the end
of my investigation.
I possess a secondary source of data that I had obtained on a website
www.edexcel.com which had been posted by the examination board. I have
chosen to use a secondary source of data, as this data ...view middle of the document...
I will then use the data
that I have acquired after using the stratified sampling to select the
number of pupils randomly and hopefully prove or disprove the
hypotheses that I have made.
Stratified sampling is a sampling method in which the population is
divided in to groups (in this case, year groups) and then random
samples are taken from each stratum (or layer). There are two ways in
which you could do stratified sampling. The first method involves
dividing the class size by the total population and then multiplying
the result by the size of the sample. The second method is dividing
the class size by a hundred and then multiplying the result by the
percentage size of the sample.
The calculations that I will have to do are to find the measures of
central tendencies, which are the estimated mean, median, mode and
range. In a frequency table, the mean would simply be multiplying the
‘mid-interval value’ by the ‘frequency’ for each column. Then find the
total of the ‘mid-interval value times frequency’ column and divide
that by the ‘frequency column’ total to then get the estimated mean.
The median is the number in the middle of the whole sequence,
presuming that the sequence is set out in ascending order. The mode is
the number which appears the most in the sequence. The range is merely
the difference between the highest number and the lowest number.
Also two other calculations that I will carry out are standard
deviation and Spearman’s rank correlation. Standard deviation is the
square root of the measure of spread that uses all the data.
Spearman’s rank correlation coefficient is a measure of the agreement
between two that has been data set. However it can also be...