Review for final AP Statistics Examination...
Terms : Hide Images
| 775519583 | Addition Rule | P(A ∪ B) = P(A) + P(A) - P(A ∩ B) aids in computing the chances of one of several events occurring at a given time. | 0 | |
| 775519584 | Alpha (α) | The probability of a Type I error. See significance level. | 1 | |
| 775519585 | Alternative Hypothesis | The hypothesis stating what the researcher is seeking evidence of. A statement of inequality. It can be written looking for the difference or change in one direction from the null hypothesis or both. | 2 | |
| 775519586 | Association | Relationship between or among variables. | 3 | |
| 775519587 | Back-Transform | The process by which values are substituted into a model of transformed data, and then reversing the transforming process to obtain the predicted value or model for nontransformed data. | 4 | |
| 775519588 | Bar Chart | A graphical display used with categorical data, where frequencies for each category are shown in vertical bars. | 5 | |
| 775519589 | Bell-Shaped | Often used to describe the normal distribution. See mound-shaped. | 6 | |
| 775519590 | Beta (β) | The probability of a Type II error. See power. | 7 | |
| 775519591 | Bias | The term for systematic deviation from the truth (parameter), caused by systematically favoring some outcomes over others. | 8 | |
| 775519592 | Biased | A sampling method is biased if it tends to produce samples that do not represent the population. | 9 | |
| 775519593 | Bimodal | A distribution with two clear peaks. | 10 | |
| 775519594 | Binomial Distribution | The probability distribution of a binomial random variable. | 11 | |
| 775519595 | Binomial Random Variable | A random variable x (a) that has a fixed number of trials of a random phenomenon n, (b) that has only two possible outcomes on each trial, (c) for which the probability of a success is constant for each trial, and (d) for which each trial is independent of other trials. | 12 | |
| 775519596 | Bins | The intervals that define the "bars" of a histrogram. | 13 | |
| 775519597 | Bivariate Data | Consists of two variables, an explanatory and a response variable, usually quantitative. | 14 | |
| 775519598 | Blinding | Practice of denying knowledge to subjects about which treatment is imposed upon them. | 15 | |
| 775519599 | Blocks | Subgroups of the experimental units that are separated by some characteristic before treatments are assigned because they may respond differently to the treatments. | 16 | |
| 775519600 | Box-And-Whisker Plot/Boxplot | A graphical display of the five-number summary of a set of data, which also shows outliers. | 17 | |
| 775519601 | Categorical Variable | A variable recorded as labels, names, or other non-numerical outcomes. | 18 | |
| 775519602 | Census | A study that observes, or attempts to observe, every individual in a population. | 19 | |
| 775519603 | Central Limit Theorem | As the size n of a simple random sample increases, the shape of the sampling distribution of x̄ tends toward being normally distributed. | 20 | |
| 775519604 | Chance Device | A mechanism used to determine random outcomes. | 21 | |
| 775519605 | Cluster Sample | A sample in which a simple random sample of heterogeneous subgroups of a population is selected. | 22 | |
| 775519606 | Clusters | Heterogeneous subgroups of a population. | 23 | |
| 775519607 | Coefficient of Determination (r²) | Percent of variation in the response variable explained by its linear relationship with the explanatory variable. | 24 | |
| 775519608 | Complement | The compliment of an event is that event not occurring. | 25 | |
| 775519609 | Complementary Randomized Design | One in which all experimental units are assigned treatments solely by chance. | 26 | |
| 775519610 | Conditional Distribution | See conditional frequencies. | 27 | |
| 775519611 | Conditional Frequencies | Relative frequencies for each cell in a two-way table relative to one variable. | 28 | |
| 775519612 | Conditional Probability | The probability of an event occurring given that another has occurred. The probability of A given that B has occurred is denoted as P(A|B). | 29 | |
| 775519613 | Confidence Intervals | Give an estimated range that is likely to contain an unknown population parameter. | 30 | |
| 775519614 | Confidence Level | The level of certainty that a population parameter exists in the calculated confidence interval. | 31 | |
| 775519615 | Confounding | The situation where the effects of two or more explanatory variables on the response variable cannot be separated. | 32 | |
| 775519616 | Confounding Variable | A variable whose effect on the response variable cannot be untangled from the effects of the treatment. | 33 | |
| 775519617 | Contingency Table | See two-way table. | 34 | |
| 775519618 | Continuous Random Variables | Those typically found by measuring, such as heights or temperatures. | 35 | |
| 775519619 | Control Group | A baseline group that may be given no treatment, a faux treatment like a placebo, or an accepted treatment that is to be compared to another. | 36 | |
| 775519620 | Control | The principle that potential sources of variation due to variables not under consideration must be reduced. | 37 | |
| 775519621 | Convenience Sample | Composed of individuals who are easily accessed or contacted. | 38 | |
| 775519622 | Correlation Coefficient (r) | A measure of the strength of a linear relationship, r=(1/(n-1))Σ((xi-x̄)/sx)((yi-ȳ)/sy). | 39 | |
| 775519623 | Critical Value | The value that the test statistic must exceed in order to reject the null hypothesis. When computing a confidence interval, the value of t* (or z*) where ±t* (or ± z*) bounds the central C% of the t (or z) distribution. | 40 | |
| 775519624 | Cumulative Frequency | The sums of the frequencies of the data values from smallest to largest. | 41 | |
| 775519625 | Data Set | Collection of observations from a sample or population. | 42 | |
| 775519626 | Dependent Events | Two events are called dependent when they are related and the fact that one event has occurred changes the probability that the second event occurs. | 43 | |
| 775519627 | Discrete Random Variables | Those usually obtained by counting. | 44 | |
| 775519628 | Disjoint Events | Events that cannot occur simultaneously. | 45 | |
| 775519629 | Distribution | Frequencies of values in a data set. | 46 | |
| 775519630 | Dotplot | A graphical display used with univariate data. Each data point is shown as a dot located above its numerical value on the horizontal axis. | 47 | |
| 775519631 | Double-Blind | When both the subjects and data gatherers are ignorant about which treatment a subject received. | 48 | |
| 775519632 | Empirical Rule (68-95-99.7) Rule | Gives benchmarks for understanding how probability is distributed under a normal curve. In the normal distribution, 68% of the observations are within one standard deviation of the mean, 95% is within two standard deviations of the mean, and 99.7% is within three standard deviations of the mean. | 49 | |
| 775519633 | Estimation | The process of determining the value of a population parameter from a sample statistic. | 50 | |
| 775519634 | Expected Value | The mean of a probability distribution. | 51 | |
| 775519635 | Experiment | A study where the researcher deliberately influences individuals by imposing conditions and determining the individuals' responses to those conditions. | 52 | |
| 775519636 | Experimental Units | Individuals (a person, a plot of land, a machine, or any single material unit) in an experiment. | 53 | |
| 775519637 | Explanatory Variable | Explains the response variable, sometimes known as the treatment variable. | 54 | |
| 775519638 | Exponential Model | A model of the form y = abˣ. | 55 | |
| 775519639 | Extrapolation | Using a model to predict values far outside the range of the explanatory variable, which is prone to creating unreasonable predictions. | 56 | |
| 775519640 | Factors | One or more explanatory variables in an experiment. | 57 | |
| 775519641 | First Quartile | Symbolized Q1, represents the median of the lower 50% of a data set. | 58 | |
| 775519642 | Five-Number Summary | The minimum, first quartile (Q1), median, third quartile (Q3), and maximum values in a data set. | 59 | |
| 775519643 | Frequency Table | A display organizing categorical or numerical data and how often each occurs. | 60 | |
| 775519644 | Geometric Distribution | The probability distribution of a geometric random variable X. All possible outcomes of X before the first success is seen and their associated probabilities. | 61 | |
| 775519645 | Geometric Random Variable | A random variable X (a) that has two possible outcomes of each trial, (b) for which the probability of a success is constant for each trial, and (c) for which each trial is independent of the other trials. | 62 | |
| 775519646 | Graphical Display | A visual representation of a distribution. | 63 | |
| 775519647 | Histogram | Used with univariate data, frequencies are shown on the vertical axis, and intervals or bins define the values on the horizontal axis. | 64 | |
| 775519648 | Independent Events | Two events are called independent when knowing that one event has occurred does not change the probability that the second event occurs. | 65 | |
| 775519649 | Independent Random Variables | If the values of one random variable have no association with the values of another, the two variables are called independent random variables. | 66 | |
| 775519650 | Influential Point | An extreme value whose removal would drastically change the slope of the least-squares regression model. | 67 | |
| 775519651 | Interquartile Range | Describes the spread of middle 50% of a data set, IQR = Q3 - Q1. | 68 | |
| 775519652 | Joint Distribution | See joint frequencies. | 69 | |
| 775519653 | Joint Frequencies | Frequencies for each cell in a two-way table relative to the total number of data. | 70 | |
| 775519654 | Law of Large Numbers | The long-term relative frequency of an event gets closer to the true relative frequency as the number of traits of random phenomenon increases. | 71 | |
| 775519655 | Least-Squares Regression Line (LSRL) | The "best-fit" line that is calculated by minimizing the sum of the squares of the differences between the observed and predicted values of the line. The LSRL has the equation ŷ = bo + b1x. | 72 | |
| 775613389 | levels | The different quantities or categories of a factor in an experiment. | 73 | |
| 775613390 | Linear Regression | A method of finding the best model for a linear relationship between the explanatory and response variable. | 74 | |
| 775613391 | Logarithmic Transformation | Procedure that changes a variable by taking the logarithm of each of its values. | 75 | |
| 775613392 | Lurking Variable | A variable that has an effect on the outcome of a study but was not part of the investigation. | 76 | |
| 775613393 | margin of Error | A range of values to the left and right of a point estimate. | 77 | |
| 775613394 | Marginal Distribution | See marginal frequencies. | 78 | |
| 775613395 | marginal Frequencies | Row totals and column totals in a two-way table. | 79 | |
| 775613396 | Matched-Pairs Design | The design of a study where experimental units are naturally paired by a common characteristic, or with themselves in a before-after type of study. | 80 | |
| 775613397 | Maximum | The largest numerical value in a data set. | 81 | |
| 775613398 | Mean | The arithmetic average of a data set; the sum of all the values divided by the number of values, x̄ = (Σxi)/n. | 82 | |
| 775613399 | Mean of a Binomial Random Variable X | μx = np. | 83 | |
| 775613400 | Mean of a Discrete Random Variable | μx = Σ from i=1 to n of xiP(xi). | 84 | |
| 775613401 | Mean of a Geometric Random Variable | μx=1/p. | 85 | |
| 775613402 | measures of Center | These locate the middle of a distribution. The mean and median are measures of center. | 86 | |
| 775613403 | Median | The middle value of a data set; the equal areas point, where 50% of the data are at or below this value, and 50% of the data are at or above this value. | 87 | |
| 775613404 | Minimum | The smallest numerical value in a data set. | 88 | |
| 775613405 | Mound-Shaped | Resembles a hill or mount; a distribution that is symmetric and unimodal. | 89 | |
| 775613406 | Multiplication Rule | P(A ∩ B) = P(A) * P(B|A) is used when we are interested in teh probability of two events occurring simultaneously, or in succession. | 90 | |
| 775613407 | Multistage Sample | A sample resulting from multiple applications of cluster, stratified, and/or simple random sampling. | 91 | |
| 775613408 | Mutually Exclusive Events | See disjoint events. | 92 | |
| 775613409 | Nonresponse Bias | The situation where an individual selected to be in the sample is unwilling, or unable, to provide data. | 93 | |
| 775613410 | Normal Distribution | A continuous probability distribution that appears in many situations, both natural and man-made. It has a bell-shape and the area under the normal density curve is always equal to 1. | 94 | |
| 775613411 | Null Hypothesis | The hypothesis of no difference, no change, and no association. A statement of equality, usually written in the form Ho: parameter = hypothesized value. | 95 | |
| 775613412 | Observational Study | Attempts to determine relationships between variables, but the researcher imposes no conditions as in an experiment. | 96 | |
| 775613413 | Observed Values | Actual outcomes or data from a study or an experiment. | 97 | |
| 775613414 | One-Way Table | A frequency table of one variable. | 98 | |
| 775613415 | Outlier | An extreme value in a data set. Quantified by being less than Q1 - 1.5*IQR or more than Q3 + 1.5*IRQ. | 99 | |
| 775613416 | Percentiles | Divide the data set into 100 equal parts. An observation at the Pth percentile is higher tha P percent of all observations. | 100 | |
| 775613417 | Placebo | A faux treatment given in an experiment that resembles the real treatment under consideration. | 101 | |
| 775613418 | Placebo Effect | A phenomenon where subjects show a response to a treatment merely because the treatment is imposed regardless of its actual effect. | 102 | |
| 775613419 | Point Estimate | An approximate value that has been calculated for the unknown parameter. | 103 | |
| 775613420 | Population | The collection of all individuals under consideration in a study. | 104 | |
| 775613421 | Population Parameter | A characteristic or measure of a population. | 105 | |
| 775613422 | Position | Location of a data value relative to the population | 106 | |
| 775613423 | Power | The probability of correctly rejecting the null hypothesis when it is in fact false. Equal to 1 - β. See beta and Type II error. | 107 | |
| 775613424 | Power Model | A function in the form of y - axᵇ. | 108 | |
| 775745343 | Predicted Value | The value of the response variable predicted by a model for a given explanatory variable. | 109 | |
| 775745344 | Probability | Describes the chance that a certain outcome of a random phenomenon will occur. | 110 | |
| 775745345 | Probability Distribution | A discrete random variable X is a function of all n possible outcomes of the random variable (xi) and their associated probabilities P(xi). | 111 | |
| 775745346 | Probability Sample | Composed of individuals selected by chance. | 112 | |
| 775745347 | P-Value | The probability of observing a test statistic as extreme as, or more extreme than, the statistic obtained from a sample, under the assumption that the null hypothesis is true. | 113 | |
| 775745348 | Quantitative | A variable whose values are counts or measurements. | 114 | |
| 775745349 | Random Digit Table | A chance device that is used to select experimental units or conduct simulations. | 115 | |
| 775745350 | Random Phenomena | Those outcomes that are unpredictable in the short term, but nevertheless, have a long-term pattern. | 116 | |
| 775745351 | Random Sample | A sample composed of individuals selected by chance. | 117 | |
| 775745352 | Random Variables | Numerical outcome of a random phenomenon. | 118 | |
| 775745353 | Randomization | The process by which treatments are assigned by a chance mechanism to the experimental units. | 119 | |
| 775745354 | Randomized Block Design | First, units are sorted into subgroups or blocks, and then treatments are randomly assigned within the blocks. | 120 | |
| 775745355 | Range | Calculated as the maximum value minus the minimum value in a data set. | 121 | |
| 775745356 | Relative Frequency | Percentage or proportion of the whole number of data. | 122 | |
| 775745357 | Replication | The practice of reducing chance variation by assigning each treatment to many experimental units. | 123 | |
| 775745358 | Residual | Observed value minus predicted value of the response variable. | 124 | |
| 775745359 | Response Bias | Because of the manner in which an interview is conducted, because of the phrasing of questions, or because of the attitude of the respondent, inaccurate data are collected. | 125 | |
| 775745360 | Response Variable | Measures the outcomes that have been observed. | 126 | |
| 775745361 | Sample | A selected subset of a population from which data are gathered. | 127 | |
| 775745362 | Sample Statistic | Result of a sample used to estimate a parameter. | 128 | |
| 775745363 | Sample Survey | A study that collects information from a sample of a population in order to determine one or more characteristics of the population. | 129 | |
| 775745364 | Sampling Distribution | The probability distribution of a sample statistic when a sample is drawn from a population. | 130 | |
| 775745365 | Sampling Distribution of the Sample Mean (x̄) | The distribution of sample means from all possible simple random samples of size n taken from a population. | 131 | |
| 775745366 | Sampling Distribution of a Sample Proportion p̂ | The distribution of sample proportions from all possible simple random samples of size n taken from a population. | 132 | |
| 775745367 | Sampling Error | See sampling variability. | 133 | |
| 776426844 | Sampling Variability | Natural variability due to the sampling process. Each possible random sample from a population will generate a different sample statistic. | 134 | |
| 776426845 | Scatterplots | Used to visualize bivariate data. The explanatory variable is shown on the horizontal axis and the response variable is shown on the vertical axis. | 135 | |
| 776426846 | Significance Level | The probability of a Type I error. A benchmark against which the P-value compared to determine if the null hypothesis will be rejected. See also alpha. | 136 | |
| 776426847 | Simple Random Sample (SRS) | A sample where n individuals are selected from a population in a way that every possible combination of n individuals is equally likely. | 137 | |
| 776426848 | Simulation | A method of modeling chance behavior that accurately mimics the situation being considered. | 138 | |
| 776426849 | Skewed | A unimodal asymmetric, distribution that tends to slant-most of the data are clustered on one side of the distribution and "tails" off on the other side. | 139 | |
| 776426850 | Standard Deviation of a Binomial Random Variable X | σₓ=√(np(1-p)). | 140 | |
| 776426851 | Standard Deviation of a Discrete Random Variable X | σₓ=√(σ²ₓ). | 141 | |
| 776426852 | Standard Deviation | Used to measure variability of a data set. It is calculated as the square root of the variance of a set of data, s = √((Σ(xi-x̄)²/(n-1)). | 142 | |
| 776426853 | Standard Error | An estimate of the standard deviation of the sampling distribution of a statistic. | 143 | |
| 776426854 | Standard Normal Probabilities | The probabilities calculated from values of the standard normal distribution. | 144 | |
| 776426855 | Standardized Score | The number of standard deviations an observation lies from the mean, z = (observation - mean) / (standard deviation). | 145 | |
| 776426856 | Statistically Significant | When a sample statistic is shown to be far from a hypothesized parameter. When the P-value is less than the significance level. | 146 | |
| 776426857 | Stemplot | Also called a stem-and-leaf plot. Data are separated into a stem and leaf by place value and organized in the form of a histogram. | 147 | |
| 776426858 | Strata | Subgroups of a population that are similar or homogeneous. | 148 | |
| 776426859 | Stratification | Part of the sampling process where units of the study are separated into strata. | 149 | |
| 776426860 | Stratified Random Sample | A sample in which simple random samples are selected from each of several homogeneous subgroups of the population, known as strata. | 150 | |
| 776426861 | Subjects | individuals in an experiment that are people. | 151 | |
| 776426862 | Symmetric | The distribution that resembles a mirror image on either side of the center. | 152 | |
| 776426863 | Systematic Random Sample | A sample where every kth individual is selected from a list or queue. | 153 | |
| 776426864 | Test Statistic | The number of standard deviations (standard errors) that a sample statistic lies from a hypothesized population parameter. | 154 | |
| 776426865 | Third Quartile | Symbolized Q3, represents the median of the upper 50% of a data set. | 155 | |
| 776426866 | Transformation | Changing the values of a data set using a mathematical operation. | 156 | |
| 776426867 | Treatments | Combinations of different levels of the factors in an experiment. | 157 | |
| 776426868 | Two-Way Table | A frequency table that displays two categorical variables. | 158 | |
| 776426869 | Type I Error | Rejecting a null hypothesis when it is in fact true. | 159 | |
| 776426870 | Type II Error | Failing to reject a null hypothesis when it is in fact false. | 160 | |
| 776426871 | Undercoverage | When some individuals of a population are not included in the sampling process. | 161 | |
| 776426872 | Uniform | All data values in the distribution have similar frequencies. | 162 | |
| 776426873 | Unimodal | A distribution with a single, clearly defined, peak. | 163 | |
| 776426874 | Univariate | One-variable data. | 164 | |
| 776426875 | Variables | Characteristics of the individuals under study. | 165 | |
| 776426876 | Variability | The spread in a data set. | 166 | |
| 776426877 | Variance | Used to measure variability, the average of the squared deviations from the mean, s²ₓ = √((Σ(xi-x̄)²/(n-1)). | 167 | |
| 776426878 | Variance of a Binomial Random Variable X | σ²ₓ - np(1-p). | 168 | |
| 776426879 | Variance of a Discrete Random Variable X | σ²ₓ = Σ from i=1 to n of (xi-μₓ)²οP(xi). | 169 | |
| 776426880 | Venn Diagram | Graphical representation of sets or outcomes and how they intersect. | 170 | |
| 776426881 | Voluntary Response Bias | Bias due to the manner in which people choose to respond to voluntary surveys. | 171 | |
| 776426882 | Voluntary Response Sample | Composed of individuals who choose to respond to a survey because of interest in the subject. | 172 | |
| 776426883 | Z-Score | See standardized score. | 173 |
