# physics and math

 .remove_background_ad { border: 1px solid #555555; padding: .75em; margin: .75em; background-color: #e7e7e7; } .rmbg_image { max-height: 80px; } median (n+1)/2, the median will be between these two numbersleast susceptible to outliers, not useful for large ranges standard distribution can be transformed from normal distributionwith zero as the mean and st. dev of 1 normal distribution all central tendency (mode, mean, median) are the same skewed distributions neg skewed distribution with tail on the left (mean towards the left, then median and then mode) bimodal distribution two or more peaks range heavily affected by outliersapprox te st. dev as 1/4 of the range interquartile range Q1=multiply n by 1/4Q3=multiply n by 3/4if whole number, quartile is the mean of the value at this position and the next highest, round up in other cases)IQR=Q3-Q1, range is 1.5(IGR) below Q1 or above Q3 outlier more than 3 st. dev away from meankey to determining whether or not the mean is an appropriate measure, could be measurement errorthrow out or not (DET before study) independent events outcomes do not impact each other mutually exclusive outcome cannot occur at the same time (one cannot flip head and tail in one throw) exhaustive no other possible outcomes probability "and" multiply the probabilities"or" add the probabilities and subtract the probably of both happening together probability of 10 births having at least one boy 1-probability of having all girls p value and significance level (alpha) if p value is greater than sign alpha, then we fail to reject the null hypothesis type 1 error report difference between two populations when there isn't one type 2 error we report no difference when there is a difference confidence report no difference when there is no difference power report difference when there is difference confidence interval reverse of hypothesis testing; instead of using p score, we use 95% confidence (30 is the mean)30-(3)(1.96) to 30+3(1.96)95% confidence that true mean value is between those two levels3 is standard dev. histograms and bar graphs histograms show distribution (mode) of variables, while bar graphs compare variables box and whisker Q1 and Q3 (Q2 median in middle line)range is 1.5(IQR) correlation could be direct, inverse but does not imply causation respect for persons honestyinformed consentconfidentiality ethics of medicine beneficencenonmaleficenceautonomyjustice justice selection of research topic and execution of researchmorally relevant differences (appropriate reasons to treat people differently): transplant more likely to give to younger individualno difference in perceived benefit between individuals, then all individuals should assume equal risk; particular population is likely to benefit that pop should assume higher proportion of risk equipoise if it becomes evidence that one treatment option is clearly superior before a study is done, then study must stop, because providing inferior treatment is a net harm. popluation complete group of every individual that satisfies the attributes of interest parameter information that is calculated using every person in a population internal validty support for causality external validity (generalizability) samples are representative of target population studies need to have what in order for intervention to be allowed statistically significantly (not the result of random chance) and clinical significance (notable or worthwhile change in health status as a result of our intervention .remove_background_ad { border: 1px solid #555555; padding: .75em; margin: .75em; background-color: #e7e7e7; } .rmbg_image { max-height: 80px; } Authorxijunzhu ID315522 Card Setphysics and math Descriptiondata based and research Updated2016-02-08T02:24:25Z Show Answers