AP Statistics Flashcards
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| 12995019328 | observational study | observes individuals and measures variables of interest but does not attempt to influence the responses | 0 | |
| 12995019329 | experiment | A research method in which an investigator manipulates one or more factors to observe the effect on some behavior or mental process (TREATMENT) | 1 | |
| 12995019330 | population | the entire group of individuals or instances about whom we hope to learn | 2 | |
| 12995019331 | sample | a subset of the population | 3 | |
| 12995019332 | census | entire population count | 4 | |
| 12995019333 | Voluntary Response Sample (VRS) | A sample which involves only those who want to participate in the sampling | 5 | |
| 12995019334 | bias | design of a statistical study systematically favors certain outcomes. | 6 | |
| 12995019335 | Simple Random Sample (SRS) | of size n consists of n individuals from the population chosen in such a way that every set of n individuals has an equal chance to be the sample actually selected | 7 | |
| 12995019336 | stratified random sample | a sample from selected subgroups of the target population in which everyone in those subgroups has an equal chance of being included in the research | 8 | |
| 12995019337 | multistage sampling | a probability sampling technique involving at least two stages: a random sample of clusters followed by a random sample of people within the selected clusters | 9 | |
| 12995019338 | cluster sample | a sampling design in which entire groups are chosen at random EX: company sending boxes of products, test 1 box and each product instead of testing products from different boxes | 10 | |
| 12995019339 | convience sample | sample chosen without any random mechanism; samples chosen based on ease of selection EX: choosing first 10 people in line at X to learn about X | 11 | |
| 12995019340 | systemic sample | select every 'nth' to participate EX: choose every 10th person in line at X | 12 | |
| 12995019341 | sampling bias | under-coverage, nonresponse, writing effect, response bias, writing effect | 13 | |
| 12995019342 | experimental units | the individuals on which the experiment is done | 14 | |
| 12995019343 | subjects | Experimental units that are human beings. | 15 | |
| 12995019344 | treatment | a specific condition applied to the individuals in an experiment | 16 | |
| 12995019345 | factors | the explanatory variables in an experiment | 17 | |
| 12995019346 | placebo | something which has a positive mental effect, but no physical effect | 18 | |
| 12995019347 | control group | In 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. | 19 | |
| 12995019348 | 3 steps of experimental design | 1. control 2. randomize 3. replicate | 20 | |
| 12995019349 | statistical significance | a statistical statement of how likely it is that an obtained result occurred by chance | 21 | |
| 12995019350 | double blind experiment | an experiment in which neither the experimenter nor the participants know which participants received which treatment | 22 | |
| 12995019351 | lack of realism | A weakness in experiments where the setting of the experiment does not realistically duplicate the conditions we really want to study. | 23 | |
| 12995019352 | block design | the random assignment of units to treatments is carried out separately within each block | 24 | |
| 12995019353 | 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. | 25 | |
| 12995019354 | confounded variable | an unintended difference between the conditions of an experiment that could have affected the dependent variable | 26 | |
| 12995019355 | completely randomized design experiment | the treatments are assigned to all the experimental units completely by chance | 27 | |
| 12995019356 | random comparative design | SRS -->treatment 1--------------> ------->trestmrnt 2---> compare! | 28 | |
| 12995019357 | simulation | A representation of a situation or problem with a similar but simpler model or a more easily manipulated model in order to determine experimental results. | 29 | |
| 12995019358 | inference procedure | educated guess | 30 | |
| 12995019359 | parameter | numerical summary of a population | 31 | |
| 12995019360 | statistic | a numerical measurement describing some characteristic of a sample | 32 | |
| 12995019361 | sampling distribution | a theoretical distribution of sample statistics | 33 | |
| 12995019362 | sampling variability | the value of a statistic varies in repeated random sampling | 34 | |
| 12995019363 | bigger the sample... | the smaller the error | 35 | |
| 12995019364 | p | population proportion | 36 | |
| 12995019365 | p(hat) | sample proportion | 37 | |
| 12995019366 | rules for sampling distribution | 1. formula (for standard deviation) only works if the population is at least 10 times as large as n 2. use normal approximations only if np > 10 AND n(1-p) > 10 | 38 | |
| 12995019367 | sample means of p(hat) | shape - normalish (np > 10 , n(1-p) > 10 center - mean=p spread - standard deviation decreases as n increases | 39 | |
| 12995019368 | sample mean (x-bar) | shape - normalish IF population is normal (they say); if n >30; if n <30, then check normal probability plot (linearish) OR check plot graph (no strong skewness) center - mean = mu spread - stigma/sq rt(n) | 40 | |
| 12995019369 | confidence interval | "I am % confident that the true mean of ___ is between ( __ , __ )" | 41 | |
| 12995019370 | probability | number of success / number of trials | 42 | |
| 12995019371 | independent | outcome of 1 trial doesn't affect or influence the outcome of another | 43 | |
| 12995019372 | probability model | A description of some chance process that consists of two parts: a sample space S and a probability for each outcome. | 44 | |
| 12995019373 | multiplication principle | When the probabilities of multiple events are multiplied together to determine the likelihood of all of those events occurring | 45 | |
| 12995019374 | can something that is mutually exclusive be independent? | no, it is dependent | 46 | |
| 12995019375 | probability distribution | list of possible outcomes with associated probabilities | 47 | |
| 12995019376 | individuals | objects described by a set of data | 48 | |
| 12995019377 | categorical data | places an individual into one of several groups or categories | 49 | |
| 12995019378 | quantitative data | Data associated with mathematical models and statistical techniques used to analyze spatial location and association. | 50 | |
| 12995019379 | SOCS | shape, outliers, center, spread | 51 | |
| 12995019380 | how to measure shape | skewness, symmetry, bimoel, uniform | 52 | |
| 12995019381 | skewed right | tail is on the right: mean > median | 53 | |
| 12995019382 | skewed left | tail is on the left | 54 | |
| 12995019383 | outliers | extreme values that don't appear to belong with the rest of the data IQR(1.5)+Q3 ; Q1-IQR(1.5) | 55 | |
| 12995019384 | how to measure center | mean, median | 56 | |
| 12995019385 | bimodel | two peaks | 57 | |
| 12995019386 | how to measure spread | 1. Range and Interquartile Range 2. Standard Deviation and variance | 58 | |
| 12995019387 | add transformation | center - move as you add spread- doesn't change | 59 | |
| 12995019388 | multiplied transformation | center - original x k spread - original x k | 60 | |
| 12995019389 | normal curve | the symmetrical bell-shaped curve that describes the distribution of many physical and psychological attributes. Most scores fall near the average, and fewer and fewer scores lie near the extremes. | 61 | |
| 12995019390 | normal distribution | mean and standard deviation | 62 | |
| 12995019391 | 68-95-99.7 rule | in a normal model, about 68% of values fall within 1 standard deviation of the mean, about 95% fall within 2 standard deviations of the mean, and about 99.7% fall within 3 standard deviations of the mean | 63 | |
| 12995019392 | z score | a measure of how many standard deviations you are away from the norm (average or mean) | 64 | |
| 12995019393 | what is needed to go from z score to probability? | normality | 65 | |
| 12995019394 | assess normality | 1. if they tell you 2. plot 3. normal probability lot | 66 | |
| 12995019395 | percentiles | Divide the data set into 100 equal parts. An observation at the Pth percentile is higher tha P percent of all observations. | 67 |