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| 9854174470 | 5 number summary | Min, Q1, Med, Q3, Max 25% of data between each number The five numbers that help describe the center, and spread of data |  | 0 |
| 9854174471 | z score | std dev from mean -Number of standard deviations a score is above or below the mean (positive above, negative below |  | 1 |
| 9854174472 | standard deviation | A 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 |
| 9854174473 | Parameter | From the whole population- usually unknown We use statistics to estimate them: |  | 3 |
| 9854174474 | categorical data | Data 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 |  | 4 |
| 9854174475 | quantitative data | Numbers that it makes sense to average age is quantitative |  | 5 |
| 9854174476 | bar graph | a 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 |
| 9854174477 | sample | A 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 arkansas |  | 7 |
| 9854174478 | random | Assigning participants to experimental and control conditions by chance. Create equal groups Assigning subjects to experimental groups based on chance. pulling names or numbers out of a hat |  | 8 |
| 9854174479 | bias | Any systematic failure of a sampling method to represent its population Any way that tampers with the accuracy of the sample |  | 9 |
| 9854174480 | Undercoverage | leaves out people...no phone...no house.... using a list that leaves people out! When some groups in the population are left out of the process of choosing the sample |  | 10 |
| 9854174481 | nonresponse | bias introduced to a sample when a large fraction of those sampled fails to respond When many people of a sample do not respond |  | 11 |
| 9854174482 | voluntary response bias | Bias introduced to a sample when individuals can choose on their own whether to participate in the sample. |  | 12 |
| 9854174483 | statistic | Application of mathematics to describing and analyzing data |  | 13 |
| 9854174484 | independent | (statistics) a variable whose values are independent of changes in the values of other variables |  | 14 |
| 9854174485 | historgram | graphical representation of a frequency distribution using vertical bars but bars touch each other to indicate variables are related | 15 | |
| 9854174486 | box plot | A 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. |  | 16 |
| 9854174487 | scatterplot | A 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). |  | 17 |
| 9854174488 | correlation | r ranging from -1 to +1 ( very linear) describes positive or negative describes how close to a line r = -.23 weak negative |  | 18 |
| 9854174489 | skewness | The 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 center |  | 19 |
| 9854174490 | variance | commons measure of spread about the mean as center std dev squared |  | 20 |
| 9854174491 | statistical significance | P value< alpha Reject the Ho Too unlikely to happen by chance alone.....something caused it! |  | 21 |
| 9854174492 | P-value | The probability of finding the sample or more extreme if the Ho was true. Small P makes us believe the Ho is not true. |  | 22 |
| 9854174493 | empirical rule | The 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 curve |  | 23 |
| 9854174494 | lurking variable | A variable that has an important effect on the relationship among the variables in a study but is not one of the explanatory variables studied |  | 24 |
| 9854174495 | null hypothesis | Ho: Hypothesis that predicts NO relationship between variables. The aim of research is to reject this hypothesis No effect No difference |  | 25 |
| 9854174496 | alternate hypothesis | Ha 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. p< alpha |  | 26 |
| 9854174497 | probability | A 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. |  | 27 |
| 9854174498 | descriptive statistics | SOCS Shape Outliers Center Spread..... CONTEXT CONTEXT CONTEXT! | 28 | |
| 9854174499 | mean | A 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. |  | 29 |
| 9854174500 | median | A 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. |  | 30 |
| 9854174501 | mode | Measure of central tendency that uses most frequently occurring score. |  | 31 |
| 9854174502 | range | Distance between highest and lowest scores in a set of data. |  | 32 |
| 9854174503 | data | Facts and statistics collected together for reference or analysis |  | 33 |
| 9854174504 | Q1 | A 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. |  | 34 |
| 9854174505 | Q3 | A 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 data |  | 35 |
| 9854174506 | minimum | (n.) the smallest possible amount; (adj.) the lowest permissible or possible | 36 | |
| 9854174507 | outlier | A value much greater or much less than the others in a data set |  | 37 |
| 9854174508 | margin of error | In statistical research, the range of outcomes we expect for a population, given the data revealed by a sample drawn from that population |  | 38 |
| 9854174509 | simple random sample | sample from the whole group...no dividing 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. |  | 39 |
| 9854174510 | sampling distribution | Distribution 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. Bigger sample...tall and skinny (less variable) |  | 40 |
| 9854174511 | stratified random sample | A method of sampling that involves dividing your population into homogeneous subgroups( like freshmen, sophomore, junior, senior) 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 stratum |  | 41 |
| 9854174512 | systematic sample | A sample drawn by selecting individuals systematically from a sampling frame ( like take every 10th person in line) 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. |  | 42 |
| 9854174513 | cluster sample | Is obtained by selecting all individuals within a randomly selected collection or group of individuals. |  | 43 |
| 9854174514 | 10% rule | a sample has to be less than 10% of the whole population Pop> 10 n (Independent assumption) | 44 | |
| 9854174515 | Extrapolation | Predicting outside the domain of the data |  | 45 |
| 9854174516 | theoretical probability | A 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 1/6 | 46 | |
| 9854174517 | binomial probability | 2 outcomes( success, failure) F ixed trials (n) I ndependent S ame prob each time (p) P(x = 3)= binompdf(n,p,3) P(x<3)= binomcdf(n,p,2)...stops at 2 | 47 | |
| 9854174518 | block design | The 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)." |  | 48 |
| 9854174519 | double blind | An 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 received |  | 49 |
| 9854174520 | placebo | A fake treatment. A chemically inert substance that produces real medical benefits because the patient believes it will help her |  | 50 |
| 9854174521 | least squares regression line | the line with the smallest sum of squared residuals |  | 51 |
| 9854174522 | type I error | Reject the Ho could result in Type 1 error We rejected the Ho...but it was right. |  | 52 |
| 9854174523 | type II error | Fail tooooooo reject the Ho....but it was wrong |  | 53 |
| 9854174524 | matched pairs | self match- you take both treatments (randomized) A....B or B...A match with someone else- one gets one treatment one gets the other |  | 54 |
| 9854174525 | conditional prabability | probability given that something else has already occurred P(B/A)= P(A&B)/P(A)....with a tree diadram or another way: drawing a 3 red cards: (26/52)(25/51)(24/50) |  | 55 |
| 9854174526 | sample space | Set of all possible outcomes of an experiment |  | 56 |
| 9854174527 | confounded variable | A 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.) |  | 57 |
| 9854174528 | marginal distribution | In the margin (ONLY USE TOTALS) |  | 58 |
| 9854174529 | coefficient of determination | r squared Represents the amount of variance accounted for by that correlation. % of variation in y explained by x | 59 | |
| 9854174530 | bimodal | A 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 modes |  | 60 |
| 9854174531 | experiment | A kind of research in which the researcher controls all the conditions and directly manipulates the conditions, including the independent variable. A treatment Can establish cause and effect |  | 61 |
| 9854174532 | law 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 statistics | 62 | |
| 9854174533 | extrapolation | calculation of the value of a function outside the range of known values | 63 | |
| 9854174534 | IQR | A measure of variability, based on dividing a data set into quartiles Q3-Q1 Spread Difference between upper and lower quartile of a boxplot | | 64 |
| 9854174535 | Confidence interval | interval that we are ____ confident captured the true mean: proportion or mean, or slope, or difference in proportion, or diff in means If 0 is not in the interval...we have sig evidence of a difference. we are 95% confident that etc. |  | 65 |
| 9854174536 | Standard Error | margin of error without the t or the z Standard deviation of sampling distribution |  | 66 |
| 9854174537 | Residual | y - yhat ex. yhat = 40 + 10x ( grade for study) a student studies 5 hrs makes a 100 would have a residual of 100- (40 + 10(5))= 10.....the student made 10 more points than we predicted. |  | 67 |
| 9854174538 | Convenience sample | Whenever a sample is taken it gives an improper results because the sample was taken from a very convenient area instead of representing a population | 68 | |
| 9854174539 | 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. | 69 | |
| 9854174540 | degrees of freedom | n-1 x2 chart (R-1)(C-1) LINREG N-2 | 70 | |
| 9854174541 | two way table | A table containing counts for two categorical variables. It has r rows and c columns. describes to categorical variables with row variable and column variable | 71 | |
| 9854174542 | spread | The visible variation in a sample distribution IQR STD DEV Range variance | 72 | |
| 9854174543 | center | The measure of the distance the mode is from the center of a distribution Mean Median |  | 73 |
| 9854174544 | shape | You tell me. |  | 74 |
| 9854174545 | discrete random variable | countable |  | 75 |
| 9854174546 | central limit theorem | As the sample size gets larger ( say 30) the distribution of the sample becomes normal. |  | 76 |
| 9854174547 | standardized value | z score t score |  | 77 |
| 9854174548 | mutually exclusive | Nothing in common disjoint never independent |  | 78 |
| 9854174549 | wording bias | Whenever a bias is created in a sample by the way the survey is worded to favor one question |  | 79 |
| 9854174572 | z test | For proportions | 80 | |
| 9854174573 | t test | For means | 81 | |
| 9854174550 | chi squared goodness of fit | tests 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 loaded |  | 82 |
| 9854174551 | frequency table | A 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. |  | 83 |
| 9854174552 | uniform | A histogram doesn't appear to have any mode and in which all the bars are approximately the same height Evenly spaced consistent; unchanging; the same for everyone |  | 84 |
| 9854174553 | symetric | When in a normal distribution both sides are identical |  | 85 |
| 9854174555 | s | standard deviation of residuals | 86 | |
| 9854174556 | r2 | overall measure of how successful the regression is in linearlly relating to y and x | 87 | |
| 9854174557 | influential point | a point when omitted will give very different results | 88 | |
| 9854174558 | census | When a survey has no sample but instead test or surveys the entire population | 89 | |
| 9854174559 | convenience sample | Choosing 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. |  | 90 |
| 9854174560 | response bias | Lying A police officer asking teenagers about drug use |  | 91 |
| 9854174561 | observational study | A study based on data in which no manipulation of factors has been employed. A study that observes characteristics of an existing population. usually a survey |  | 92 |
| 9854174562 | prospective study | an observational study in which subjects are followed to observe future outcomes |  | 93 |
| 9854174563 | 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. |  | 94 |
| 9854174564 | blinding | Subject does not know treatment 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. |  | 95 |
| 9854174565 | placebo effect | Experimental 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. | | 96 |
| 9854174566 | trial | A performed experiment based upon the hypothesis you made. |  | 97 |
| 9854174567 | maximum | (n.) the greatest possible amount or degree in a data sample the largest value in a set of data | 98 | |
| 9854174568 | Assumptions for X2 Test | Random SRS Selection LSS E>5 Independent Pop > 10n |  | 99 |
| 9854174569 | 3 important experimental factors | 1. Control- blocking, blind, dblind, placebo 2. Random: # all and select at random(like random table) 3. Replication: Did you do enough to minimize results from chance? |  | 100 |
