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115944556825 number summaryThe minumum value, lower quartile, median, upper quartile, and maximum value for a data set. These five values give a summary of the shape of the distribution and are used to make box plots. The five numbers that help describe the center, spread and shape of data0
11594455683z scorea measure of how many standard deviations you are away from the norm (average or mean) -Number of standard deviations a score is above or below the mean (positive above, negative below1
11594455684standard deviationA statistical measure of how far away each value is, on average, from the mean. A measure of spread. Specifically, the typical distance the data points are from the mean.2
11594455685population(statistics) the entire aggregation of items from which samples can be drawn What the sample in an experiment or study usually reperesents3
11594455686categorical dataData that can be placed into categories . For example "gender" is a categorical data and the categories are "male" and "female". Labels or names used to identify categories of like items If you asked people in which month they were born or what their favorite class is, they would answer with names, which would be categorical data. However, if you asked them how many siblings they have, they would answer with numbers, not categories Labels or names used to identify categories of like items4
11594455687quantitative dataData associated with mathematical models and statistical techniques used to analyze spatial location and association. numerical information describing how much, how little, how big, how tall, how fast, etc. age is quantitative5
11594455688bar grapha type of graph in which the lengths of bars are used to represent and compare data in categories A graph that uses horizontal or vertical bars to represent data.6
11594455689parameter(n) a determining or characteristic element; a factor that shapes the total outcome; a limit, boundary a characteristic or constant factor something that determines the limits of certain data values7
11594455690sampleA relatively small proportion of people who are chosen in a survey so as to be representative of the whole. a small part of a population that represents the whole A survey in star city representing the entire state of arkansas8
11594455691randomAssigning participants to experimental and control conditions by chance, thus minimizing preexisting differences between those assigned to the different groups. Assigning subjects to expenrimental groups based on chance. pulling names or numbers out of a hat9
11594455692biasAny systematic failure of a sampling method to represent its population Any way that tampers with the accuracy of the sample10
11594455693UndercoverageA sampling scheme that biases the sample in a way that gives a part of the population less representation than it has in the population. When some groups in the population are left out of the process of choosing the sample11
11594455694nonresponsebias introduced to a sample when a large fraction of those sampled fails to respond When many people of a sample do not respond12
11594455695voluntary response biasBias introduced to a sample when individuals can choose on their own whether to participate in the sample.13
11594455696statisticApplication of mathematics to describing and analyzing data14
11594455697independent(statistics) a variable whose values are independent of changes in the values of other variables15
11594455698historgramgraphical representation of a frequency distribution using vertical bars but bars touch each other to indicate variables are related16
11594455699box plotA dsiplay that shows the distribution of values in a data set seperated into four equal-sized groups. A box plot is constructed from the five number summary of the data.17
11594455700scatterplotA graphed cluster of dots, each of which represents the values of two variables. The slope of the points suggests the direction of the relationship between the two variables. The amount of scatter suggests the strength of the correlation (little scatter indicates high correlation).18
11594455701correlationA measure of the extent to which two factors vary together, and thus of how well either factor predicts the other. The correlation coefficient is the mathematical expression of the relationship, ranging from -1 to +119
11594455702skewnessThe extent to which cases are clustered more at one or the other end of the distribution of a quantitative variable rather than in a symmetric pattern around its center20
11594455703variencecommons measure of spread about the mean as center21
11594455704statistical significanceA statistical statement of how likely it is that an obtained result occurred by chance/The condition that exists when the probability that the observed findings are due to chance is very low22
11594455705P-valueA measure of statistical significance. The lower, the more likely the results of an experiment did not occur simply chance.23
11594455706empirical ruleThe rules gives the approximate % of observations w/in 1 standard deviation (68%), 2 standard deviations (95%) and 3 standard deviations (99.7%) of the mean when the histogram is well approx. by a normal curve24
11594455707lurking variableA variable that has an important effect on the relationship among the variables in a study but is not one of the explanatory variables studied25
11594455708null hypothesisHypothesis that predicts NO relationship between variables. The aim of research is to reject this hypothesis26
11594455709alternate hypothesis, is the hypothesis to be considered as an alternative to the null hypothesis. The null hypothesis will be rejected in favor of the Ha only if the sample data strongly indicate that the null hypothesis is false.27
11594455710quota sampleA sample deliberately constructed to reflect several of the major characteristics of a given population28
11594455711probabilityA number with a value from 0 to 1 that describes the likelihood that an event will occur. example, if a bag contains a red marble, a white marble and a blue marble then the probability of selecting a red marble is 1/3.29
11594455712descriptive statisticsMathematical procedures for organizing collections of data, such as determining the mean, the median, the range, the variance, and the correlation coefficient30
11594455713meanA measure of center in a set of numerical data, computed by adding the values in a list and then dividing by the number of values in the list.31
11594455714medianA measure of center in a set of numerical data. The median of a list of values is the value appearing at the center of a sorted version of the list - or the mean of the two central values if the list contains an even number of values.32
11594455715modeMeasure of central tendency that uses most frequently occurring score.33
11594455716rangeDistance between highest and lowest scores in a set of data.34
11594455717dataFacts and statistics collected together for reference or analysis35
11594455718Q1A location measure of the data such that has one fourth or 25% of the data is smaller than it. Found by dividing the ordered data set in half (excluding the middle observation if n is odd) and finding the median of the lower half of the data.36
11594455719Q3A location to measeure when counting data to such as the median where instead of counting 50% it is 75% from the beginning of the sorted data37
11594455720minimum(n.) the smallest possible amount; (adj.) the lowest permissible or possible38
11594455721outlierA value much greater or much less than the others in a data set39
11594455722margin of errorIn statistical research, the range of outcomes we expect for a population, given the data revealed by a sample drawn from that population40
11594455723statistical normalscoring the middle of the bell-curve; low, moderate, or high scoring41
11594455724simple random sampleA sample selected in such a way that every element in the population or sampling frame has an equal probability of being chosen. Equivalently, all samples of size n have an equal chance of being selected. A sample of size n selected from the population in such a way that each possible sample of size n has an equal chance of being selected.42
11594455725sampling distributionDistribution of sample proportions from sample to sample. A sampling distribution of a sample statistic for a fixed sample size n is the distribution of that statistic derived from every possible sample of size n for a given population. A distribution of statistics obtained by selecting all the possible samples of a specific size from a population43
11594455726stratified random sampleA method of sampling that involves dividing your population into homogeneous subgroups and taking a simple random sample in each subgroup. a sampling design in which the population is divided into several groups, and random samples are then drawn from each stratum44
11594455727systematic sampleA sample drawn by selecting individuals systematically from a sampling frame A sample drawn by selecting individuals systematically from a sampling frame. When there is no relationship between the order of the sampling frame and the variables of interest, a systematic sample can be representative.45
11594455728cluster sampleIs obtained by selecting all individuals within a randomly selected collection or group of individuals.46
1159445572910% rulea sample has to be lass than 10% of the whole population47
11594455730InterpolationThe estimation of an unknown number between known numbers. Interpolation is a way of approximating price or yield using bond tables that do not give the net yield on every amount invested at every rate of interest and for every maturity.48
11594455731QualitativeData in the form of recorded descriptions rather than numerical measurements.49
11594455732theoretical probabilityA probability obtained by analyzing a situation. If all of the outcomes are equally likely, you can find the theoretical probability of an event by listing all of the possible outcomes and then finding the ratio of the number of outcomes producing the desired event to the total number of outcomes. For example, there are 36 possible equally likely outcomes (number pairs) when two fair number cubes are rolled. of these six have a sum of 7, so the probability of rolling a sum of 7 is 6/36 or 1/650
11594455788experimental probability51
11594455733block designThe subjects in an experiment are first divided into groups (called 'blocks') based on some common characteristic (such as gender) that is hypothesised to have an effect on the response. Randomization of treatments then happens within each block (each block is like its own mini-experiment)."52
11594455734blindingThe practice of concealing group assignment from study subjects, investigators, and/or those who assess subject outcomes, typically in the context of a randomized controlled trial. For ex, study subjects may receive capsules with identical appearance and taste; however, the treatment group receives the active drug, whereas the control group receives the placebo.53
11594455735double blindAn experiment in which neither the subjects nor the people who work with them know which treatment each subject is receiving Neither the subjects nor the people who have contact with them know which treatment a subject received54
11594455736placeboA fake treatment. A chemically inert substance that produces real medical benefits because the patient believes it will help her55
11594455737least squares regression linethe line with the smallest sum of squared residuals56
11594455738type I errorAn error that occurs when a researcher concludes that the independent variable had an effect on the dependent variable, when no such relation exists; a "false positive57
11594455739type II errorAn error that occurs when a researcher concludes that the independent variable had no effect on the dependent variable, when in truth it did; a "false negative58
11594455789joint frequency59
11594455740matched pairsan observational technique that involves matching each participant in the experimental group with a specific participant in the control group in order to eliminate the possibility that a third variable (and not the independent variable) caused changes in the dependent variable60
11594455741conditional prababilityprobability given that something else has already occurred61
11594455742sample spaceSet of all possible outcomes of an experiment62
11594455743confounded variableA variable whose effect on the response variable cannot be separated from the effect of the explanatory variable on the response variable. (Note: Usually confounded variables are lurking variables but only a few lurking variables are also confounded.)63
11594455744marginal frequencyA set of intervals, usually adjacent and of equal width, into which the range of a statistical distribution is divided, each associated with a frequency indicating the number of measurements in that interval.64
11594455745coefficient of determinationThe statistic or number determined by squaring the correlation coefficient. Represents the amount of variance accounted for by that correlation. Statistic that represents amount of variance accounted for by a correlation.65
11594455746binomialA two-name naming system.66
11594455747unimodalhaving one mode; this is a useful term for describing the shape of a histogram when it's generally mound-shaped a data set with one mode such a normal distribution usually has only one mode67
11594455748bimodalA type of distribution, where there is two or more categories with an equal count or cases and with more cases than the other categories. A distribution with two modes68
11594455749experimentA kind of research in which the researcher controls all the conditions and directly manipulates the conditions, including the independent variable. Testing the hypothesis69
11594455750law of large numbers(statistics) law stating that a large number of items taken at random from a population will (on the average) have the population statistics70
11594455751extrapolationcalculation of the value of a function outside the range of known values71
11594455752snowballHuyen wanted to conduct market research to find out why students were unhappy with Marketing 431, probably the finest course ever to be offered by a university. In order to do this she needed to find people who were unhappy with the course. Figuring that these people would talk to each other, she used a sampling technique where she found one person who was unhappy with the course and, after asking her research questions, asked this person for the name of another person who was unhappy with the course.72
11594455753IQRA measure of variability, based on dividing a data set into quartiles Difference between upper and lower quartile of a boxplot73
11594455754Confidence intervalA range of values for a variable of interest; the specified probability is called the confidence level and the end points of the confidence interval are called the confidence limits A range of numbers in which most of the data values are likely to fall. we are 95% confident that etc.74
11594455755Standard ErrorA statistic providing an estimate of the possible magnitude to error. The larger the standard error of measurement, the less reliable the score. Standard deviation of sampling distribution75
11594455790Residual76
11594455756Convenience sampleWhenever a sample is taken it gives an improper results because the sample was taken from a very convenient area instead of representing a population77
11594455757simulationA representation of a situation or problem with a similar but simpler model or a more easily manipulated model in order to determine experimental results.78
11594455758degrees of freedomThe number of individual scores that can vary without changing the sample mean. Statistically written as 'N-1' where N represents the number of subjects.79
11594455759two way tableA table containing counts for two categorical variables. It has r rows and c columns. describes to categorical variables with row variable and column variable80
11594455760spreadThe visible variation in a sample distribution81
11594455761centerThe measure of the distance the mode is from the center of a distribution82
11594455791shape83
11594455792discrete random variable84
11594455793central limit theorem85
11594455794standardized value86
11594455795mutually exclusive87
11594455762wording biasWhenever a bias is created in a sample by the way the survey is worded to favor one question88
11594455796causation89
11594455797z test90
11594455798t test91
11594455763chi squared goodness of fittests how well close the observes data is to what would be expected under the model. If a sign diff is found b/w the two then ob. data has not been generated by chance. nominal data Determine if scores from one variable match expectations for that distribution a gambler placed $1,000 into a game of greed in which he lost. He hopes to catch his opponent and bust him for loading the dice. He does this by choosing one dice to roll 36 times. He knows that the each side has an equal chance of landing face up. He hopes to get an outcome abnormal to this. Given the data below, can we prove that the dice are loaded92
11594455764frequency tableA grouping of qualitative data into mutually exclusive classes showing the number of observations in each class. A chart showing the number of times a specific event happens.93
11594455765area principlethe area occupied by a part of the graph should correspond to the magnitude of the value it represents94
11594455799simpsons paradox95
11594455766contingency tabledisplays counts, and, sometimes, percentages of individuals falling into named categories on two or more variables. The table categorizes the individuals on all variables at once, to reveal possible patterns in one variable that may be contingent on the category of the other. A two-variable table with cross-tabulated data.96
11594455767stem and leaf displayA multiple column table depicting the individual digits of the scores. A score of 95 would have a stem of 9 and a leaf of 5, a score of 62 would have a stem of 6 and a leaf of 2. If a particular stem has more than one leaf, such as the scores 54, 58, and 51, the stem of 5 has three leaves, in this case 458. . It shows the range of values of the variable97
11594455768multimodalDescribes a graph of quantitative data with more than two clear peaks. A distribution with more than two modes98
11594455769uniformA histogram doesn't appear to have any mode and in which all the bars are approximately the same height Evenly spaced99
11594455770symetricWhen in a normal distribution both sides are identical100
11594455771time plotDisplays data that change over time. Often, successive values are connected with lines to show trends more clearly. Sometimes a smooth curve is added to the plot to help show long-term patterns and trends. Displays data that change over time.101
11594455772sestandard deviation of residuals102
11594455773r2overall measure of how successful the regression is in linearlly relating to y and x103
11594455800leverage104
11594455774influential pointa point when omitted will give very different results105
11594455775censusWhen a survey has no sample but instead test or surveys the entire population106
11594455801multistage samole107
11594455776pilotsmall trial run of a survey to see if questions are clear108
11594455777convenience sampleChoosing a sample because it is convenient. failing to get a proper representation of the population because If you survey everyone on your soccer team who attends tonight's practice, you are surveying a convenience sample.109
11594455778response biasAnything in a survey design that influences responses falls under the heading of response bias. One typical response bias arises from the wording of questions, which may suggest a favored response. Voters, for example, are more likely to express support of "the president" than support of the particular person holding that office at the moment. Anything that changes the response in a survey A police officer asking teenagers about drug use110
11594455779observational studyA study based on data in which no manipulation of factors has been employed. A study that observes characteristics of an existing population. usually a survey111
11594455780retrospective studyWhat study examines whether a past association exists between an exposure of interest and development of a present condition? data are collected from the past by going back in time112
11594455781prospective studyan observational study in which subjects are followed to observe future outcomes113
11594455782statistic factorA multifactor model in which statistical methods are applied ot a set of historical returns to determine portfolios that best explain either historical return covariances or variances.114
11594455783control groupIn an experiment, the group that is not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment.115
11594455784blindingThe practice of concealing group assignment from study subjects, investigators, and/or those who assess subject outcomes, typically in the context of a randomized controlled trial. For ex, study subjects may receive capsules with identical appearance and taste; however, the treatment group receives the active drug, whereas the control group receives the placebo.116
11594455785placebo effectExperimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition, which is assumed to be an active agent.117
11594455786trialA performed experiment based upon the hypothesis you made.118
11594455787maximum(n.) the greatest possible amount or degree in a data sample the largest value in a set of data119

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