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Can you use the TI-83 (plus) calculators to create a frequency histogram with uneven classes? (we call it a frequency density graph) If so, how? (I'm not sure how to input the ranges, for example, the range is 0-30, 30-40, 40-60 etc. I have calculated the frequency density itself I'm just not sure how to create the graph on a calculator.)

I really need more answers for my survey, my IA deadline is soon, I hope you can fill out my survey really quick!!! https://docs.google.com/forms/d/e/1FAIpQLSe7IuEph8ScgYcmxBfkcb0tid41fV1i1mycGQ-WJdw5q2s2Zw/viewform?usp=sf_link Thank you for your time!

Hello, If my biology IA data has a linearly decreasing graph but my statistical test shows the data is insignificant, is my IA wasted?

Just incase anybody wanted to know the average grades/scores that students internationally receive in IB, I've found a PDF with statistics from IBO - this is the most recent PDF I could find and the statistics have been taken from the May 2016 session. I've listed the page numbers of some information depending on what you may want to check - Page 9: Extended Essay statistics Page 10: TOK statistics Page 16: Statistics on number of points awarded to candidates Page 17 to Page 22: All subject grade distributions (including mean grade + % of candidates receiving grades) PDF Download: dp-statistical-bulletin-may-2016-en.pdf Link: http://www.ibo.org/contentassets/bc850970f4e54b87828f83c7976a4db6/dp-statistical-bulletin-may-2016-en.pdf

Hi, Could anyone please explain how to solve this type of question: In a ski resort, the probability of more than 3 accidents in any day at the weekend (Saturday and Sunday) is 0.24. Assuming a Poisson model, 1) Calculate the mean number of accidents per day at the weekend (Saturday and Sunday) I got to the point that P(x>3) =0.24 and P(x<3 or x=3) = 0.76. How do I continue from here? I also know that the answer is 2.49. 2) Calculate the probabilit that, in the four weekends in February, there will be more than 5 accidents during at least two of the weekends. I am completely lost as to how to approach this question. Any help (with clear explanations) is much appreciated. Thanks!

Hello guys, please complete the questionnaire and post the results. If you have a better way for me to do this, please don't mind telling me. Thank you very much!!! Maths golden ration questionairre.docx

I'm doing my IA on the correlation between MBTI and genetic inheritance, which simply saying about inheriting personality traits, but I'm not sure if it's enough for SL though. My teacher said that if I use sth from math studies IB will like it, cuz it's from different level, so i joined their lessons to learn sth we didn't from statistics, but i've just read somewhere on this forum that correlation is not enough for SL. Is it so? If yes, what could I possibly add or change not to score badly? I've just started my experiment, which you can take part in btw (https://docs.google.com/forms/d/e/1FAIpQLSc5kBERe3yBDE5TUlfjVenmXL3pO_JyQlSJcCLXQZ25HP5-sQ/viewform?c=0&w=1), so i wouldn't like to change my whole topic Do you have any advice?

After finishing my IA I realized that my data points failed me. I was testing to see if ethylene had any effect on seed germination, but I rarely even got more than three germination's in a trial. Can I turn in an IA that doesn't have any calculations done because the data wasn't adequate? Or is that not an Internal Assessment?

So about how long do your teachers give you to work on the IA? My class started them around mid-early October. We turned in our first rough draft, emphasis on rough, last week and our teacher want them in this week as the copy she sends to IB, and she hasn't fully helped us or explained what else had to be done to fix them. Does this sound like the right timeline, or is she really cutting short our time? Any last minute tips?

I am having a hard time figuring out what statistics test to use for my Math SL IA. I am exploring whether or not caffeine has an effect on athletic agility. I have a control group, a placebo, and the real caffeine supplement. There are 5 subjects who will each perform three tests, three times. I figured I would average each trial for each test to have a better sample but I am having a lot of trouble on what statistics to run. Please help. I am in dire need.

Hi Guys! I am comparing Life Expectancy and GDP for my IA, and the problem is, that the data does not really look linear, but logarithmic. I get a strong moderate r value, but the teacher says since the data is not linear, I need to find another function. Anyone had this problem before and has a solution and some relevant math processes for this data? Any help is much appreciated

So we are doing a practice IA and it's to determine the elastic recoil of blood vessels?? I had the recoil and extension of arteries and veins and also the max weight for both of them. What stats test should I use?

Hi, can someone please help me solve this problem? It is part of the HL Option Statistics and Probability

If Z~N(0,1), prove that for positive k: P(|Z|<k) = 2 - 2Φ(k). I'm pretty certain the 2 - 2Φ(k) part comes from symmetry with the distribution if Φ(k) is negative. Pretty tough question but here's my working. Hoping someone can develop this further... Thanks

So I counted the colonies since I was testing bacterial growth using paper discs each plate I used had a control and I had three plates so 3 control plates So should I use the T test to compare the different antibacterial organisms to the control?

Hey everyone, Our experiments for our IAs are starting soon and I am not sure which statistical analysis to use - here is my experimental method and idea so far (haven't checked it with my teacher yet, any improvements or suggestions are welcome!) To look at how pollution affects plant growth I want to investigate the affects of acid rain on seed germination. I would do this by growing my own cress, but watering the different cress plants (in separate pots) with water of different pH, so to simulate normal rain water I would use water of 5.6 (pH) and to simulate acid rain I would use a pH of 4 or lower. I am not really sure yet how I will split the plants up and how to measure the effects other than observing but once again, if you have any advice, that would help me a lot! Now to my actual question: How do I analyse my results statistically? I was thinking of using the t-test but I am horrible at statistical analysis. Thank you!

Hi guys, I am not too sure how to structure an EE, my supervisor is one of those people who is stuck up and not willing to helpful unfortunately. Also, I am a little confused on whether the whole EE is based on just facts and figures and if not what kind of discussions are included? PS: I am doing a world studies ee on the syrian refugee crisis and its impact on germany

So I´m currently on a 2 week break from school so I wanted to take enough time to come up with a good topic for my IA. I want to do it about the recent terrorist attacks and some of the comments from the republican candidates (saying that muslims shouldn´t enter the country because they might be terrorists). I planned on doing something related to correlation or probability, but I´ve read that those topics are not strong enough for sl. Should I add something else? I haven´t seen calculus in my course but maybe I could use it in my exploration aswell... But i dont know. Should I look for another topic?

Hello!! I am writing my psychology IA right now, but now I'm at the result section and I don't understand a thing! My teacher does not explain this well, and he doesn't seem to be certain about what he's doing. There was actually a few people last year who failed their psychology, mainly because of their IAs so I'm a bit terrified! I'm a HL student, so I will need inferential statistics but how does that actually work?? For example, my teacher said I should use the General Linear Model, but I don't know if I'm allowed to use that.. I haven't found anyone who have used it before, but it does calculated the level of significance. Also, do I need a graph or something similar for the inferential part? (I already have graphs in the descriptive statistics section of the essay) Thank you so much in advance!

Hello I am currently finishing up my IA for Biology HL. I have 5 conditions one of which is control. Each with 5 trials measured over 4 time periods. With 3 dimensions to my research, I was wondering what statistical tests I should use. I was thinking of doing ANOVA and HOC test to check the difference between the conditions with each trial. 4 times ofcourse due to 4 time periods. Is this a good choice? What else should I use. Can I simply use a online calculator for this test, reference it and give the table that shows the results and then explain what the results tell me for the ANOVA and the HOC test? Some details: I tested the antimicrobial properties of turmeric at different concentration. Measuring radius of influence over 4 time periods. Also, what are the ethical concerns associated with microbials - bacteria? (not safety but ethical because I heard from my teacher that they were very strict about ethical concers even for microbials but i cant seem to think a reason for so) Thank You

Hello I am currently completing my IA in psychology HL. I am conducting an independent design study to collect ratio data (speed in km/h). I was wondering what kind of statistical tests I should use? one that I expect to use is the t test (should I do the paired or the unpaired t test?). What else should I use? If you must know, I am replicating Loftus and Palmer: Reconstruction of automobile destruction Thank You

Hi! I'm having a bit of a problem finding data for my math IA and was wondering if anyone has any ideas? My topic is about the correlation between digit ratio and GPA, but honestly I'll change it to a correlation between digit ratio and anything that I can find data on. So far all I'm finding are studies, but not much in the way of raw data

Hey guys, I'm doing my Psychology IA on the Anderson and Pichert experiment. Basically, in this study 20 participants were made to read out a story and they were each assigned a schema of either a house buyer (10) or a burglar (10). After reading the story, they had to recall the information about the house in the story from their assigned schema. After a small distraction task, the schemas of the participants were switched. 10 participants remained with their previous schema while the rest 10 were given the opposite schema. Their recalls were tested again. I used an independent measures sample and the recall questionnaires were scored out of 20 points. What inferential statical test should I use and how do I operate http://faculty.vassar.edu/lowry/VassarStats.html Thank you so much!

Hi everyone! I was just wondering how to write the paragraph about inferential statistics in my IA. I did all of the math (I think) and figured out the significance level and which hypothesis to reject and accept, but I don't know what two-tailed or one-tailed means (my teacher wants it in the paragraph). Here is exactly what my teacher said to put in the paragraph: Analysis of Results: This information is used to decide the level of significance that was achieved in the study. You must justify why you chose your statistical test. Words like one-tailed, non-parametric and type of data (ordinal, nominal, and interval) should be used. Information like the critical value should be mentioned as well as the p < or > 0.01 or 0.05 should be mentioned in this section but calculations should be in the appendix. Then you must state whether the findings indicated true significance. The results were found to be significant (p<0.05) which means that the probability of the results occurring by chance if the null hypothesis is true is less than 5%. Therefore, the null hypothesis was rejected and the research hypothesis was accepted. If you cannot reject the null hypothesis, than you cannot make any real decision about your research hypothesis and this will be explored in the discussion section. Sorry if this question doesn't make any sense, but I really need help Thanks in advanced!

Hi everyone! I was just wondering how to write the paragraph about inferential statistics in my IA. I did all of the math (I think) and figured out the significance level and which hypothesis to reject and accept, but I don't know what two-tailed or one-tailed means (my teacher wants it in the paragraph). Here is exactly what my teacher said to put in the paragraph: Analysis of Results: This information is used to decide the level of significance that was achieved in the study. You must justify why you chose your statistical test. Words like one-tailed, non-parametric and type of data (ordinal, nominal, and interval) should be used. Information like the critical value should be mentioned as well as the p < or > 0.01 or 0.05 should be mentioned in this section but calculations should be in the appendix. Then you must state whether the findings indicated true significance. The results were found to be significant (p<0.05) which means that the probability of the results occurring by chance if the null hypothesis is true is less than 5%. Therefore, the null hypothesis was rejected and the research hypothesis was accepted. If you cannot reject the null hypothesis, than you cannot make any real decision about your research hypothesis and this will be explored in the discussion section. Sorry if this question doesn't make any sense, but I really need help Thanks in advanced!