1216 words - 5 pages

A population may contain separate groups or strata. Each group needs to be fairly represented in the sample. The number from each group is proportional to the group size. The selection is then made at random from each group, this is called stratified sampling, and I need to use this to make sure my results represents each group fairly, the equation I need to use is:No. Of pupils in specific data X Sample No.Total No. Of pupilsStratified SamplingYr 10 boys= 106/ 370 X 60= 17Yr 10 girls= 99/370 X 60= 15Yr 11 boys= 84/370 X =14Yr 11 girls= 86/370 X 14Boys= 17+14=31Girls= 15+14=29Now from this I will randomly pick my sample of 60 pupils because it is big enough to represent the whole school, I will do this using my calculator by pressing 370Ran# this will give me a random number in decimals I will then round it off. If a number comes up more than once I will ignore it. I will now keep going until I have a full set of data.Collecting The DataAs I have already mentioned in my introduction, I will use a sample of 60 students. Upon using the random sampling sample. I realised that I would need 31 boys and 29 girls to fairly represent each group.BoysHeight Weight1.9 701.6 501.6 471.68 591.8 721.77 591.72 621.75 451.75 571.57 491.73 571.54 541.63 561.61 561.65 471.65 551.6 511.67 661.72 511.65 421.69 51.75 601.7 722 601.86 801.51 381.57 541.61 451.5 451.52 441.62 51Here are all the boys to be included in my sample below are all the girls to be included.GirlsHeight Weight1.73 511.62 481.7 481.6 501.8 601.51 361.52 701.61 541.67 481.7 551.71 541.55 551.6 561.75 571.8 501.72 601.67 481.7 541.65 451.69 421.62 541.73 481.62 501.52 451.5 351.74 501.52 441.96 931.75 68Scatter DiagramScatter diagram is used to see if there are connections between two sets of data, for my data the scatter diagram will see if there are any connections between height and weight, I will do three scatter diagrams, one for boys, one for girls and one for mixed gender. I can then analyse the graphs to see whether there is any connection and compare them.(see Page )Cumulative FrequencyA cumulative frequency diagram shows how the cumulative frequency changes as the data values increase. The data is shown on a continuous scale on the horizontal axis. The cumulative frequency is shown on the vertical axis. You plot the upper ends of each group against the cumulative frequency. You then join the points with straight lines or a curve. Below are the tally charts for the cumulative frequency.Mixed HeightClass Interval Frequency Cumulative Frequency150≤x160≤x170≤x180≤x190≤x200≤xMixed WeightClass Interval Frequency Cumulative Frequency0≤x20≤x40≤x60≤x80≤xAbove is the cumulative table for mixed gender height and weight I will now do it for Boys.Boys HeightClass Interval Frequency Cumulative Frequency150≤x160≤x170≤x180≤x190≤x200≤xBoys WeightClass Interval Frequency Cumulative Frequency0≤x20≤x40≤x60≤x80≤xI will now do the same for...

Get inspired and start your paper now!