AP Statistics Vocabulary Flashcards
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| 6072909969 | Symmetric | data on which both sides are fairly the same shape and size. "Bell Curve" | 0 | |
| 6072909970 | Parameter | value of a population (typically unknown) | 1 | |
| 6072909971 | Statistic | a calculated value about a population from a sample(s). | 2 | |
| 6072909972 | Median | the middle point of the data (50th percentile) when the data is in numerical order. | 3 | |
| 6072909973 | Variability | allows statisticians to distinguish between usual and unusual occurrences. | 4 | |
| 6072909974 | Standard Deviation | measures the typical or average deviation of observations from the mean | 5 | |
| 6072909975 | Skewed Right | mean is a larger value than the median. |  | 6 |
| 6072909976 | Z-score/T-score | is a standardized score. This tells you how many standard deviations from the mean an observation is. | 7 | |
| 6072909977 | Normal Model | is a bell shaped and symmetrical curve. As σ increases the curve flattens. As σ decreases the curve thins. | 8 | |
| 6072909978 | Mutually Exclusive | A and B have no intersection. They cannot happen at the same time. |  | 9 |
| 6072909979 | Independent | if knowing one event does not change the outcome of another. | 10 | |
| 6072909980 | Law of Large Numbers | as an experiment is repeated the experimental probability gets closer and closer to the true (theoretical) probability. | 11 | |
| 6072909981 | Correlation Coefficient (r) | is a quantitative assessment of the strength and direction of a linear relationship. between -1 and 1. | 12 | |
| 6072909982 | Least Squares Regression Line (LSRL) | is a line of mathematical best fit. Minimizes the deviations (residuals) from the line. Used with bivariate data. | 13 | |
| 6072909983 | Residual (error) | is vertical difference of a point from the LSRL. They should all add to zero. Is the difference between the observed and expected value. | 14 | |
| 6072909984 | Coefficient of Determination (r-squared) | gives the proportion of variation in y (response) that is explained by the relationship of (x, y). | 15 | |
| 6072909985 | Extrapolation | LRSL cannot be used to find values outside of the range of the original data. |  | 16 |
| 6072909986 | Influential Points | are points that if removed significantly change the LSRL. |  | 17 |
| 6072909987 | Census | a complete count of the population. Disadvantages of this: Not accurate, Expensive, Impossible to do | 18 | |
| 6072909988 | Simple Random Sample | one chooses so that each unit has an equal chance and every set of units has an equal chance of being selected. |  | 19 |
| 6072909989 | Stratified Sampling | divide the population into homogeneous groups then SRS from every group. [Observational studies] |  | 20 |
| 6072909990 | Cluster Sampling | Usually can be based on location. Select a random location and sample ALL at that location. Divide the population into heterogeneous groups and SRS a certain amount of groups. Take all members/things in that group. | 21 | |
| 6072909991 | Bias | favors a certain outcome, has to do with center of sampling distributions - if centered over true parameter then considered unbiased |  | 22 |
| 6072909992 | Voluntary Response Bias | people choose themselves to participate. | 23 | |
| 6072909993 | Convenience Sampling | ask people who are easy, friendly, or comfortable asking. | 24 | |
| 6072909994 | Undercoverage | some group(s) are left out of the selection process. | 25 | |
| 6072909995 | Nonresponse Bias | someone cannot or does not want to be contacted or participate. | 26 | |
| 6072909996 | Control Group | a group used to compare the factor to for effectiveness - does NOT have to be placebo | 27 | |
| 6072909997 | Single Blind | a method used so that the subjects are unaware of the treatment (who gets a placebo or the real treatment). | 28 | |
| 6072909998 | Double Blind | neither the subjects nor the evaluators know which treatment is being given. | 29 | |
| 6072909999 | Replication | A MUST for EVERY experimental design. Uses many subjects to quantify the natural variation in the response. | 30 | |
| 6072910000 | Completely Randomized Design | all units are allocated to all of the treatments randomly [Experiment] |  | 31 |
| 6072910001 | Randomized Block | units are separated based on a KNOWN factor. Then randomly assign treatments in each group -reduces variation |  | 32 |
| 6072910002 | Matched-Pair Design | Once a pair receives a certain treatment, then the other pair automatically receives the second treatment. OR individuals do both treatments in random order (before/after or pretest/post-test) Assignment is dependent | 33 | |
| 6072910003 | Confounding Variables | are where the effect of the variable on the response cannot be separated from the effects of the factor being tested - happens in observational studies - when you use random assignment to treatments you do NOT have this! | 34 | |
| 6072910004 | Randomization | reduces bias by spreading extraneous variables to all groups in the experiment. MUST have in EVERY experiment | 35 | |
| 6072910005 | Binomial Probability | Trials have two outcomes; Trials are independent; and most importantly, the number of trials are fixed! | 36 | |
| 6072910006 | Geometric Probability | two mutually exclusive outcomes, each trial is independent, probability (p) of success is the same for all trials. (NOT a fixed number of trials) | 37 | |
| 6072910007 | Sampling Distribution | is the distribution of all possible values of all possible samples. Use normalcdf to calculate probabilities | 38 | |
| 6072910009 | Central Limit Theorem | when n is sufficiently large (n > 30) the sampLING distribution is approximately normal even if the population distribution is not normal. |  | 39 |
| 6072910024 | Lurking Variable | is a variable that is not included as an explanatory or response variable in the analysis but can affect the interpretation of relationships between variables. It can falsely identify a strong relationship between variables or it can hide the true relationship. | 40 | |
| 6072910026 | Simulation | is a way to model random events, such that simulated outcomes closely match real-world outcomes | 41 | |
| 6072910027 | Placebo effect | A remarkable phenomenon in which a fake treatment, can sometimes improve a patient's condition simply because the person has the expectation that it will be helpful | 42 | |
| 6072910029 | Histogram | A graphical display that represents a frequency distribution by means of rectangles whose widths represent class intervals or "bins" | 43 | |
| 6076074473 | Interquartile Range | A numerical description of a distribution requires both a measure of center and a measure of spread | 44 | |
| 6076095619 | "X bar" | Sample mean | 45 | |
| 6076112187 | 68-95-99.7 rule | percentage of data within 1, 2, and 3 standard deviations of a normally distributed dataset. | 46 | |
| 6076166190 | Explanatory variable | Helps explain or influence change in a response variable | 47 | |
| 6076169340 | Response variable | Measures an outcome of a study | 48 | |
| 6076211219 | Treatment | A specific condition applied to the individuals in an experiment. | 49 | |
| 6076237161 | "p hat" | Sample proportion used to estimate unknown parameter | 50 | |
| 6076293023 | unbiased estimator | A statistic used to estimate a parameter, if the mean of its sampling distribution is equal to the value of the parameter being estimated. | 51 |