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  • Mantel-Haenszel
  • For $2\times 2\times K$ tables, we use Taylor expansion to study the biases and variances of the Mantel-Haenszel estimator and modified Mantel-Haenszel estimators of the common odds ratio using one pair of pseudotables for data without missing values and for data with missing values, based either on the completely observed subsample or on estimated cell means when both stratum and column variables are always observed. (umd.edu)
  • Analytic studies and simulation results show that the Mantel-Haenszel estimators overestimate the common odds ratio but adding one pair of pseudotables reduces bias and variance. (umd.edu)
  • outcome
  • Diagnostic odds ratios less than one indicate that the test can be improved by simply inverting the outcome of the test - the test is in the wrong direction, while a diagnostic odds ratio of exactly one means that the test is equally likely to predict a positive outcome whatever the true condition - the test gives no information. (wikipedia.org)
  • Binary
  • In medical testing with binary classification, the diagnostic odds ratio is a measure of the effectiveness of a diagnostic test. (wikipedia.org)
  • Sensitivity and specificity Binary classification Positive predictive value and negative predictive value Odds ratio Glas, Afina S. (wikipedia.org)
  • The odds ratio may be viewed as an association measure between binary variables, and it is defined as follows. (r-bloggers.com)
  • For simplicity, suppose x and y are two binary variables of interest and assume that they are coded so that they each take the values 0 or 1 - this assumption is easily relaxed, as discussed below, but it simplifies the basic description of the odds ratio. (r-bloggers.com)
  • Further, if x and y are two statistically independent binary random variables, it can be shown that the odds ratio is equal to 1. (r-bloggers.com)
  • assumption
  • This assumption states that the odds of preferring one class over another do not depend on the presence or absence of other "irrelevant" alternatives. (wikipedia.org)
  • statistic
  • The rationale for the diagnostic odds ratio is that it is a single indicator of test performance (like accuracy and Youden's J statistic) but which is independent of prevalence (unlike accuracy) and is presented as an odds ratio, which is familiar to medical practitioners. (wikipedia.org)
  • Odds ratio is the key statistic for most case-control studies. (statsdirect.com)
  • data
  • Traditional meta-analytic techniques such as inverse-variance weighting can be used to combine log diagnostic odds ratios computed from a number of data sources to produce an overall diagnostic odds ratio for the test in question. (wikipedia.org)
  • From these data we have evidence that the odds of developing oral cancer is around two and a half times higher for heavy smokers compared with lighter (less than 16 per day) or non-smokers of cigarettes. (statsdirect.com)
  • greater
  • Odds are fairly easy to visualise when they are greater than one, but are less easily grasped when the value is less than one. (bmj.com)
  • An indicator of fleece type in sheep, the greater the ratio the finer the fleece. (thefreedictionary.com)
  • An odds ratio greater than 1 indicates that the odds of a positive response are higher in row 1 than in row 2. (sas.com)
  • The diagnostic odds ratio ranges from zero to infinity, although for useful tests it is greater than one, and higher diagnostic odds ratios are indicative of better test performance. (wikipedia.org)
  • The odds of disease among those who had ever smoked were 3.6 fold greater than among those who never smoked. (ctspedia.org)
  • Thus
  • Thus x/(x + y) is a proportion, x:y is a ratio. (thefreedictionary.com)
  • Now if the option of a red bus is introduced, a person may be indifferent between a red and a blue bus, and hence may exhibit a car : blue bus : red bus odds ratio of 1 : 0.5 : 0.5, thus maintaining a 1 : 1 ratio of car : any bus while adopting a changed car : blue bus ratio of 1 : 0.5. (wikipedia.org)
  • contrast
  • In contrast, the odds of an event is the number of those who experience the event divided by the number of those who do not. (bmj.com)
  • disease
  • The odds in favor of a particular disease occurring in an exposed group are divided by the odds in favor of its occurring in an unexposed group. (thefreedictionary.com)
  • The odds of disease were lower by a factor of 0.35 in those taking the active drug compared to those on placebo. (ctspedia.org)
  • less
  • An odds of 0.2 however seems less intuitive: 0.2 people will experience the event for every one that does not. (bmj.com)
  • Conversely, odds ratio values less than 1 imply that the variables x and y are more likely to disagree: records with y = 1 are more likely to have x = 0 than x = 1, and those with y = 0 are more likely to have x = 1 than x = 0. (r-bloggers.com)
  • desirable
  • A desirable property of an adjusted ratio estimate is collapsibility, wherein the combined crude ratio will not change after adjusting for a variable that is not a confounder. (mdpi.com)
  • value
  • When the row and column variables are independent, the true value of the odds ratio equals 1. (sas.com)
  • For most types of effect size, a larger absolute value always indicates a stronger effect, with the main exception being if the effect size is an odds ratio. (wikipedia.org)
  • The same equation can be used for estimating the odds from an experimentally obtained value of the mean. (wikipedia.org)
  • measure
  • Odds ratios are a common measure of the size of an effect and may be reported in case-control studies, cohort studies, or clinical trials. (bmj.com)
  • The diagnostic odds ratio is undefined when the number of false negatives or false positives is zero - if both false negatives and false positives are zero, then the test is perfect, but if only one is, this ratio does not give a usable measure. (wikipedia.org)
  • The odds ratio provides a simple quantitative association measure for these variables that allows us to make these comparisons directly. (r-bloggers.com)
  • The term effect size can refer to a standardized measure of effect (such as r, Cohen's d, or the odds ratio), or to an unstandardized measure (e.g., the difference between group means or the unstandardized regression coefficients). (wikipedia.org)
  • table
  • With informative missingness, estimators based on the estimated cell means do not converge to the correct common odds ratio under sparse asymptotics, and converge slowly for the large table asymptotics. (umd.edu)
  • This table is produced by the ODDSRATIO option in the MODEL statement. (sas.com)
  • standard
  • the ratio between the rate (of mortality or some such parameter) in one group of animals and the rate in another group, used as a standard and the comparison expressed as a ratio. (thefreedictionary.com)
  • smaller
  • The asymptotic variance formula of the ratio estimators had smaller biases and variances than those based on jackknifing or bootstrapping. (umd.edu)
  • given
  • In statistics, the odds ratio (OR) is one of three main ways to quantify how strongly the presence or absence of property A is associated with the presence or absence of property B in a given population. (wikipedia.org)
  • practice
  • His stance puts him at odds not just with pedagogic practice over the last few centuries but also with a tradition going back to antiquity. (wikipedia.org)
  • The fact that this often fails in practice due to the Sharpe ratio of risky assets exceeding the ratio of the volatility of the stochastic discount factor to its expectation is known as the equity premium puzzle. (wikipedia.org)
  • lower
  • This is no surprise because fossil fuels have lower 13C/12C ratios than the atmosphere. (realclimate.org)
  • Results Adjusting for individual socioeconomic and demographic characteristics, women living in neighbourhoods where poverty decreased over the 40-year period had lower odds of depressive symptoms and a greater sense of control than women living in long-term, low-poverty neighbourhoods. (bmj.com)
  • years
  • A byproduct of this work is that we also have a very nice record of atmospheric 13C variations through time, and what we find is that at no time in the last 10,000 years are the 13C/12C ratios in the atmosphere as low as they are today. (realclimate.org)
  • Rate Ratio = Incidence Rate 1 Incidence Rate 2 {\displaystyle {\text{Rate Ratio}}={\frac {\text{Incidence Rate 1}}{\text{Incidence Rate 2}}}} Where incidence rate is the occurrence of an event over person-time, for example person-years. (wikipedia.org)
  • time
  • The decrease in the 13C/12C ratio can also be observed in century long time series of corals and sclerosponges from tropical reefs. (realclimate.org)
  • After the completion of the 2006 Tour, winner Floyd Landis was found to have an elevated testosterone to epitestosterone ratio on a sample taken following Stage 17 of the race, and at the time of the 2007 Tour prologue. (wikipedia.org)
  • school
  • In boys (but not girls), school neighborhood design was significantly associated with cycling: i.e., boys attending schools in neighborhoods with high connectivity and low traffic were 5.58 times more likely to cycle (95% CI 1.11-27.96) and for each kilometer boys lived from school the odds of cycling reduced by 0.70 (95% CI 0.63-0.99). (biomedcentral.com)
  • The student-faculty ratio at Touro College is 17:1, and the school has 87.3 percent of its classes with fewer than 20 students. (wikipedia.org)
  • results
  • In fact, it can be shown that the unconditional analysis of matched pair data results in an estimate of the odds ratio which is the square of the correct, conditional one. (wikipedia.org)
  • significant
  • We find that private, inherited truncating SNVs in conserved genes are enriched in probands (odds ratio = 1.14, P = 0.0002) in comparison to unaffected siblings, an effect involving significant maternal transmission bias to sons. (nih.gov)
  • often
  • There is no commonly accepted threshold in terms of a ratio or percentage of hands played, but a "tight" player will often choose to fold weaker hands, while a "loose" player will bet on more of these hands and thus play more hands to the show/showdown. (wikipedia.org)