Mayfield High School girl/boy height/weight investigation.

Mayfield High School - GCSE Maths Coursework

Hypothesis: I believe that taller students will be heavier than shorter students. I also believe that males will be taller than females. I am investigating these topics because it is a common idea that this is true, and I am interested in proving or disproving them.

Plan: To test my hypothesis I need to sample a certain number of school students. I intend to sample the school population of Mayfield High School, taking a percentage of the 1183 students. I am only taking a percentage of those 1183 to keep the data to a manageable extent. To sample this data, I will use a stratified sampling method, and then calculate different averages of the data, for example mode, median, range, to help demonstrate the typical student. I can also put the data into Box Plots and Scatter Diagrams. This will help to obtain the accuracy of my data, and help me form a strong conclusion to relate to my Hypothesis, and find out if my data correlates well or not.

I will find these averages, as they are quick to do and will help me to find out what the typical student is like. Eventually, I will put the data into stem and leaf diagrams - this will aid me to find the mode, median, and range values in an easy way, and also so I will be able to understand it more clearly. Another aim is to draw a scatter diagram because it is a good way of comparing two variables to see if there is any correlation (pattern) between them. When I have these values, I will write a conclusion to say whether my hypothesis was correct or incorrect.

Systematic Sample: To allow me to collect 30 data points from the entire population of 1183 students, I will do it by starting with the 8th value, and counting up to the next 8th value, until I have successfully acquired 30 results.

This is Shown on the following page:

I will now plot these results in a scatter diagram to see if my results correlate (following page)

Conclusion Of My Results

I have been unsuccessful in obtaining a clear correlation, however, I can see a slight positive pattern in the graph, but this is not enough information to back up my hypothesis on ...

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This is Shown on the following page:

I will now plot these results in a scatter diagram to see if my results correlate (following page)

Conclusion Of My Results

I have been unsuccessful in obtaining a clear correlation, however, I can see a slight positive pattern in the graph, but this is not enough information to back up my hypothesis on this investigation into the height and weight of various students.

Therefore, the graph showed me that my hypothesis was incorrect. I need to look at the reasons why there was such a weak correlation…

· All my results are of different genders

· All my results are of different ages

This means that overall, the method I used to collate the students was unfair and impractical…a student in year 7 will weigh different to a student in year 9.

To try and solve this problem, I will plot more graphs to see if it does make a difference that my results were from males and females and of different ages.

The following graphs, I will set by using the same year (year 7) and by creating two separate graphs, one for male gender, and the other for female.

Samples For 15 Males In Year 7 (height and Weight)

Samples For 15 Females In Year 7 (height and Weight)

These results are plotted on scatter graphs on the following page, so once again, I can look for any patterns or correlation in my results.

Overall Conclusion

Once again, my graphs do not show a strong correlation, i.e. - no relationship between height and weight. My hypothesis was therefore incorrect, and there is no relationship between the height and weight of the students whom attend Mayfield High School.

New Hypothesis

I believe that in general, males are taller than females. I will test this by creating stem and leaf diagrams in Microsoft Excel, to compare the heights of the males and females. After doing this I will aim to find the upper quartile, and lower quartile, mode median and ranges. This will help me to plot box plots so I can again compare my results, and aim to find a relationship between the height and genders of the males and females.

MALE HEIGHT

Key: 13|6 = 1.36 kg

For the male stem and leaf diagram I have found:

· Mode - 1.42, 1.52 (as I have a number of mode values, I will not be using this to help me)

· Upper Quartile - 1.55

· Lower Quartile - 1.42

· Range - 0.28

· Mean - 1.50

FEMALE HEIGHT

Key: 14|2 = 1.42 kg

For the Female stem and leaf diagram I have found:

· Mode - 1.48, 1.59, 1.61, 1.63

· Upper Quartile - 1.62

· Lower Quartile - 1.51

· Range - 0.23

· Median - 1.59

I will now create stem and leaf diagrams to show the Weights of both the males and Females in year 7…

MALE WEIGHT

Key: 2|5 = 25 m

For the male stem and leaf diagram I have found:

· Mode - 45

· Upper Quartile - 45

· Lower Quartile - 38

· Range - 28

· Median - 43

FEMALE WEIGHT

Key: 3|9 = 39 m

For the Female stem and leaf diagram I have found:

· Mode - 45, 50

· Upper Quartile - 50

· Lower Quartile - 41

· Range - 15

· Median - 45

Conclusion

From looking at the height results i.e mod, median, ranges etc. I realised that the male mode and median are both close to each other (Near 1.50) this also applies to the female weight being around the same area.

The weight results don't really tell me anything, apart from I clearly notice that the modes for both female and male are similar (45)

I will now use the results I have found to make box plots for the research that I have done… ( These box plots are on the following page)

Overall Conclusion of this Investigation

My research has proven that the females in year 7 are not only taller than the males in their year, but they also weigh more. My box plots show this clearly.

Evaluation

I know why my results have turned out like they have. I chose to investigate the year 7 students, from the beginning. However, I did not take into account that females begin to grow before males do, this is a perfect example as in year 7, children have just began to grow resulting in both, height and weight being extremely varied.

If I was to repeat this investigation, I would choose another year to investigate, as after a few years children have grown to their typical height.