After I eventually gained all these random numbers I was able to enter it into the Mayfield high database and find all the relevant information for each people with the corresponding number, such as weight and height. This meant I could now continue with testing my hypotheses.
1st Hypothesis – Boys on average be taller then girls
To test this hypothesis I would need to look at a specific year and split it into the 2 different genders. I would then enter the heights for the boys and girls into separate stem and leaf diagrams and compare them. Firstly though I would need to highlight the heights of both the year 8 boys and year 8 girls in accumulative frequency graphs:
Heights for year 8 boys
Now I have highlighted the heights of both the year 8 boys and girls I am now going to plot these in individual stem and leaf diagrams, places them both in the same diagram and comparing them. By doing this I can clearly see whether the evidence shown in these diagrams supports my hypothesis:
Here are the stem and leaf diagrams I plotted for the heights of the year 8 boys (on the left) and the year 8 girls (on the right). It appears that these diagrams support my first hypothesis being that boys are on average taller then girls but I can’t be sure. To make a clearer comparison I would need to plot a stem and leaf diagram with both the year 8 boys and girls heights, I have done this below:
1st Hypothesis – Conclusion
By doing this stem and leaf diagram for both the year 8 boys and girls heights, I can clearly note that boys on average do in fact seem to be within the higher sections of the stem and leaf diagram. This meant that I proved my hypothesis was correct that boys would be taller the girls.
2nd Hypothesis - Boys on average weight more then girls
For my next hypothesis, I want to compare another variable amongst boys and girls, this will be like with my first hypothesis but with weight. This hypothesis will be boys on average weight more then girls. Again, like before I will create an accumulative frequency table for both year 9 girls and boys and their weights. I will then plots these in box plots and make a clear comparison of the two to see if it proves or disproves my hypothesis.
Weights of year 9 boys
Weights of year 9 girls
Now I am going to compare the values of weights for boys and girls in year 9. I’ve decided to use box plots for this hypothesis so I can clearly see the median, lower quartile value and upper quartile value. This means I can clearly compare boy’s weights to girls.
Here is the first box plot I done for the boys. This shows that the median weight for the year 9 boys is 50 (kg), with the lower quartile being 47 and the higher being 55.
Here is the next box plot for the girls. This shows that the median weight for the year 9 girls is 50, with the lower quartile being 47 and the higher being 57.
Here is the final box plot I done where I placed both the boxes for the girls and boys so I could get a clearer comparison of the median, upper quartile and lower quartile value of their weights.
2nd Hypothesis - Conclusion
By doing this I found that the median weight for both boys and girls was in fact 50. This meant I had clear evidence which actually disproves my hypothesis of boys weighing more then girls.
3rd Hypothesis - As boys get older they weight more
For my next hypothesis I chose to do a comparison of boys only. I decided to compare two different year groups look at their weights as oppose to their ages. My hypothesis was therefore as boys get older they weight more. Once again I will put the values this time of the year 7 and 11 boys weights into cumulative frequency graphs before creating histograms.
Year 7 boy’s weights
Year 11 boy’s weights
This time I am going to use histograms so I can easily note and eventually compare the weights of the year 7 and 11 boys, which will be represented by bars, making it easy to notice the differences.
Here is the first histogram I drew, showing the weights for all the 15 boys in year 7, with the highest being 56 and lowest being 31.
Here is the next histogram I drew for the year 11 boys weights, with the highest being 76 and the lowest being 45.
Here is the final histogram I drew, comparing both the year 7 boy’s weights and year 11 boys’ weights on the same scale. By doing this I could clearly see if the year 11 boys were in fact heavier then the year 7 boys.
3rd Hypothesis – Conclusion
I found by comparing my histograms that the boys in year 11 were in fact heavier then the boys in year 7, as there bars were generally higher up the scale. This meant that I had proved my hypothesis was correct.
4th Hypothesis – The taller the person the more they will weigh
Now I have conducted three hypotheses I must do one more. I would now like to make a clear comparison with height and weight, therefore my hypothesis will the taller the person, the more they weigh. Once again I will need to make a frequency table for each the year 11 boys and girls for there heights and weights. I will then create scatter graphs and plot them with the heights and weights from the tables. I will then finally compare the results with each other.
Heights and weights of year 11 boys
Heights and weights or year 11 girls
This graph slightly supports
My fourth hypothesis as it appears that the heaviest students of the year 11 boys do weigh the most. However other plots on the graph also disprove this and show that even the taller students can way little. To help find more evidence that supports my hypothesis I need to plot another graph for the year 11 girls.
This graph actually appears to disprove my hypothesis clearly, more so then my first graph. This is because it shows that the year 11 girls who are of about average height, weigh the most. To be completely sure of my results however, I will need to do another comparison of the boys and girls with another graph.
Here is my final scatter graph, which plots are colour coordinated so I can clearly see the weights of the year 11 boys (blue) and year 11 girls (blue) and then compare them.
4th Hypothesis - Conclusion
By doing this I found if you include the majority of both the boys and girls of this graph the plots are fairly mixed. This means that the graph shows a variation in both the student’s heights and weights and therefore disproves my fourth hypothesis.
I have now conducted four relevant hypotheses and used individual graphs and tables to test them. My hypotheses were quite different therefore allowing me to use a range of different graphs and methods of comparison. I felt that the evidence I provided for each hypothesis was generally quite clear and easy to understand, therefore making this coursework quite successful.