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    (Original post by leo_4_four)
    for the planning i did a random sampling test with quadrats and compared the heights of plants which indicated growth with the distance between them and then made a correlation between the two at the end. Though the "means" I'm referring to which i found the wrong values are not in the 3rd question but in the 2nd question with the number of red blood cells, and i was wondering if they'd cut marks from my graph as well besides the loosing of 2 marks for the values of the means from before or will they follow-through with my values and won't penalize my graph?
    i am not sure but i dont think they will. they will only make sure that you plotted the points correctly. also in the planning did u only divide the area into 2 parts plants that r close and plants that r far or did u take varying distances and wht stastical test did u use
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    I used varying distances including too close and too far away and i did a correlation test (Spearman's Rank) , the 3rd question is the only one we can't really compare though because each one did a different experiment and it will be correct if someone did a t-test and had a different but valid experiment to back it up, there's really no point in discussing the 3rd question though.
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    do you remember what means for red blood cells you found?
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    ya i did the same thing i just wanted to make sure it is correct as no one in my class used varying distances
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    the means for the red blood cell were 5.12 and 5.48 i think
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    wht did u get
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    yes that's the correct ones i don't know what went wrong with my calculations it was a very simple average to calculate i might have misplaced a decimal or omitted a number when typing it in my calculator , i found 6.1 for after exercise and the before i don't even remember but i think it's wrong as well because 5.1 doesn't ring a bell...that's why I'm worried i hope i loose only 2 marks for the values and they won't hopefully penalize my bar charts even though with the wrong values
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    do u have to add *10^12 after finding the mean and do u think they will penalise for it cause i didnt write that
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    no you don't because it was given in the form of "mean number of r.b.c. x10^12 after exercise: 5.4"
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    also wht did u write for the systematic errors for the beetroot experiment
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    (Original post by leo_4_four)
    no you don't because it was given in the form of "mean number of r.b.c. x10^12 after exercise: 5.4"
    LOL I must have missed that, and I thought I was lucky to have spotted that I left out the x10^12 while I was checking my paper at the last minute

    :facepalm:
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    i did with diff distance
    test-spearman test caz u will get a scatter graph...but da table/presentation crap..dont know wat 2 write..??
    ya abt da 1st quest it waz totali unexpectd!! wat a shock!!
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    I'm totally unsubscribing from all June 2010 Biology 6B threads before I get a heart attack lol.
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    (Original post by mohero)
    did any one choose varying distances for the planning or only near and far and what statistical test did u choose
    yes i chose 3 distances! 30 , 50 and 80 cm and i used a t test. i made a mess of the quadrats though cz i only used 1x1m and just counted the plants in each one
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    Wht about the systematic error question anyone?
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    (Original post by jpm)
    i did with diff distance
    test-spearman test caz u will get a scatter graph...but da table/presentation crap..dont know wat 2 write..??
    ya abt da 1st quest it waz totali unexpectd!! wat a shock!!
    i didi it with a difference test... i mentioned the Mann Whitney U test :confused: i think it was supposed to be a double investigation like that banded snails thing the first two ques were too easy though... weren't they
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    (Original post by leo_4_four)
    I used varying distances including too close and too far away and i did a correlation test (Spearman's Rank) , the 3rd question is the only one we can't really compare though because each one did a different experiment and it will be correct if someone did a t-test and had a different but valid experiment to back it up, there's really no point in discussing the 3rd question though.
    Would a correlation test work though? because it said if plants were close together they wouldn't grow well and if they were too far apart they wouldn't either so the graph wouldn't resemble that of a linear correlation one.
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    (Original post by mohero)
    Wht about the systematic error question anyone?
    I said the colorimeter had to be calibrated and stirring the solution before putting it into the colorimeter (for even pigment distribution) but I'm not sure if it's right
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    @the double investigation.

    I sort of did that.

    Three days after planting, I measure the number of germinated seedlings [emerged].

    Then four weeks after planting, I measured the number of adult plants.

    Then in my table I recorded two sets of data and carried out TWO correlation test. To see if there is a correlation between the distance and seedlings and the distance and adult plants. That's what I read in the question.

    Anyways, I prolly got like 12/24 for this question because even though I had a nice plan for the experiment I was pushed for time so I don't know how well my thoughts were transferred to the paper and don't even ask how I managed to write about how I will use my data is 3 minutes >_>
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    @calibration

    They asked what could be done to reduce systematic errors when measuring the dependent variable (that is, color intensity).

    -I mentioned calibrating the colorimeter ONCE before measuring all samples. Setting zero absorbance to water [words to that effect] and shaking tubes before testing.

    Maybe we could have mentioned washing the beetroot pieces but systematic error is usually when something is wrong with a measuring device and the error is always constant in each error measurement [and obviously the first thing that comes to mind here is the colorimeter being calibrated incorrectly].
 
 
 
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