Chapter 5 of The Practice of Statistics (Yates, Moore, and Starnes) edition 2.
Terms : Hide Images
| 5153130396 | sample | representative of an entire population; a picture of the population disturbed as little as possible by the act of gathering information; the part of the population actually examined in order to gather information | 0 | |
| 5153130397 | observational study | observes individuals and measures variables of interest, but does not attempt to influence the responses | 1 | |
| 5153130398 | experiment | deliberately imposing some treatment on individuals in order to observe their responses | 2 | |
| 5153130399 | confounded | mixed up with; condition of explanatory and lurking variables | 3 | |
| 5153130400 | simulation | provides an alternative method for producing data when observing individuals directly is too difficult | 4 | |
| 5153130401 | statistical inference | producing data to answer specific questions with a known degree of confidence | 5 | |
| 5153130402 | population | the entire group of individuals that we want information about | 6 | |
| 5153130403 | sampling | studying a part in order to gain information about the whole | 7 | |
| 5153130404 | census | attempts to contact every individual in the entire population; one of two ways of collecting data | 8 | |
| 5153130405 | design | the method used to choose the sample from the population | 9 | |
| 5153130406 | voluntary response sample | people who choose themselves by responding to a general appeal; biased because people with strong opinions, especially negative opinions, are most likely to respond; one type of bad sample design | 10 | |
| 5153130407 | convenience sampling | chooses individuals easiest to reach; one type of bad sample design; does not represent the entire population | 11 | |
| 5153130408 | bias | systematic error, favoring some parts of the population over others; systematically favors certain outcomes | 12 | |
| 5153130409 | simple random sample (SRS) | 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; gives every sample and individual a chance to be chosen to avoid bias | 13 | |
| 5153130410 | table of random digits | a long string of the digits so that each entry is equally likely to be any of digits 0 through 9; these are independent entries | 14 | |
| 5153130411 | probability sample | a sample chosen by chance. We must know what samples are possible and what chance each possible sample has | 15 | |
| 5153130412 | stratified random sample | divide population into groups; combine SRS to form full sample | 16 | |
| 5153130413 | strata | groups of similar individuals; choose a separate SRS from each sample and combine these to form the full sample | 17 | |
| 5153130414 | multistage sampling design | clusters of nearby households that an interviewer can easily visit | 18 | |
| 5153130415 | nonresponse | individual cannot be contacted or refuses to cooperate, often 30% or more | 19 | |
| 5153130416 | undercoverage | some groups in population are left out of the process of choosing the sample | 20 | |
| 5153130417 | response bias | if respondents lie, resulting in underestimation about the presence of the behavior in a population, or if an interviewer somehow conveys the more desirable answer, also influenced by race and sex, or if asked of past event, run the risk of faulty memory. lessened by supervision and no variation among interviewers | 21 | |
| 5153130418 | wording of questions | influences the answers on a survey; confusing or leading questions introduce strong bias or change an outcome | 22 | |
| 5153130419 | probability | laws that govern chance behavior | 23 | |
| 5153130420 | sampling frame | list of individuals from which a sample is actually selected | 24 | |
| 5153130421 | multistage sample | select successively smaller groups within the population in stages | 25 | |
| 5153130422 | factors | the explanatory variables in an experiment | 26 | |
| 5153130423 | level | specific value combined, forming each treatment for each of the factors | 27 | |
| 5153130424 | placebo | ... | 28 | |
| 5153130425 | experimental units | the individuals on which the experiments are done | 29 | |
| 5153130426 | subjects | when the units are human beings, they are these | 30 | |
| 5153130427 | treatment | specific experimental condition applied to the units | 31 | |
| 5153130428 | control group | enables experimenters to control the effects of outside variables on the outcome | 32 | |
| 5153130429 | 1st principle of statistical design | control effects of lurking variables on the response by comparing 2 or more treatments | 33 | |
| 5153130430 | 2nd principle of statistical design | randomize- use impersonal chance to assign experimental units to treatments | 34 | |
| 5153130431 | 3rd principle of statistical design | replicate each treatment on many units to reduce chance variation in results | 35 | |
| 5153130432 | statistically significant | an observed effect so large that it would rarely occur by chance | 36 | |
| 5153130433 | completely randomized | when all experimental units are allocated at random among all treatments | 37 | |
| 5153130434 | double blind | neither the subjects nor the people who have contact with them know which treatment a subject received | 38 | |
| 5153130435 | lack of realism | subjects or treatment or setting of an experiment may not realistically duplicate the conditions wanted for study | 39 | |
| 5153130436 | matched pairs of design | an example of block designs, whereby it reduces the effect of variations among the data by using the principles of comparison of treatments, randomisation, and replication on several experimental units | 40 | |
| 5153130437 | block | a group of experimental units or subjects that are known before the experiment to be similar in some way that is expected to affect the response to the treatments | 41 | |
| 5153130438 | block design | random assignment of units to treatments carried out separately within each block | 42 |
