Terms : Hide Images
| 5176096920 | Population | The entire group of individuals about which we want information | 0 | |
| 5176096921 | Sample | The part of the population from which we actually collect information. We use this info to draw conclusions about the entire population. | 1 | |
| 5176096922 | Sample Survey | A survey which is carried out using a sampling method, i.e. in which a portion only, and not the whole population is surveyed. | 2 | |
| 5176096923 | Convenience Sample | Choosing individuals who are easiest to reach...almost guaranteed to show bias. | 3 | |
| 5176096924 | Bias | Using a method that will consistently overestimate or underestimate the value you want to know. This design of a statistical study systematically favors certain outcomes. | 4 | |
| 5176096925 | Voluntary Response Sample | Consists of people who choose themselves by responding to a general appeal. Show bias because people with strong opnions are the most likely to respond. | 5 | |
| 5176096926 | Random Sampling | Use of chance to select a sample. This is the central principle of statistical sampling. | 6 | |
| 5176096927 | Simple Random Sample (SRS) | The simplest way to use chance to select a sample e.g. place names in a hat and draw names. Consists of size (n) 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 | |
| 5176096928 | Table of Random Digits | A long string of the digits 0, 1,2,3,4,5,6,7,8,9 with the following properties: 1) Each entry in the table is equally likely to be any of the 10 digits 0 thru 9. 2) The entries are independent of each other..Knowledge of one part of the table gives no info about any other part. | 8 | |
| 5176096929 | Stratified Random Sample | Classify the population into homogeneous groups and then choose a separate SRS in each group and combine to form a full sample. | 9 | |
| 5176096930 | Cluster Sample | Classify the population into heterogeneous groups and then choose a SRS of some of of the groups, using every individual in the selected groups. | 10 | |
| 5176096931 | Inference | The process of drawing conclusions about a population on the bais of sample data | 11 | |
| 5176096932 | Margin of Error | An amount (usually small) that is allowed for in case of miscalculation or change of circumstances. | 12 | |
| 5176096933 | Sampling Frame | List of individuals from which a sample is drawn. | 13 | |
| 5176096934 | Undercoverage | Occurs when some groups in the population are left out of the process of choosing the sample. | 14 | |
| 5176096935 | Nonresponse | Occurs when an idividual chosen for the sample can't be contacted or refuses to participate. It is the single biggest problem for sample surveys. | 15 | |
| 5176096936 | Response Bias | Caused by a systematic pattern of incorrect responses in a sample survey | 16 | |
| 5176096937 | Observational Study | A sample survey where individuals are observed and variables of interest are measured w/o an attempt to influence the response. | 17 | |
| 5176096938 | Experiment | Deliberately imposes some treatment on individuals to measure their responses. They are the only source of fully convincing data when your goal is to understand cause and effect. | 18 | |
| 5176096939 | Response Variable | Measures the outcome of a study | 19 | |
| 5176096940 | Lurking Variable | A variable that is not among the explanatory or response variables in a study but may influence the response variable. | 20 | |
| 5176096941 | Confounding | Occurs when 2 variables are associated in such a way that their effects on a response variable cannot be distinguished from each other. | 21 | |
| 5176096942 | Treatment | A specific condition applied to the individuals in an experiment. | 22 | |
| 5176096943 | Experimental Units | Smallest collection of individuals to which treatments are applied. If human, they are called subjects. | 23 | |
| 5176096944 | Factors | The explanatory variables in an experiment | 24 | |
| 5176096945 | Comparative Experiment | Compare 2 or more treatments | 25 | |
| 5176096946 | Random Assignment | Experimental units are assigned to treatments at random, using some sort of chance process | 26 | |
| 5176096947 | Completely Randomized Design | Treatments are assigned to all experimental units completely by chance | 27 | |
| 5176096948 | Control Group | Provides a baseline for comparing the effects of the other treatments. | 28 | |
| 5176096949 | What are the 3 principles of Experimental Design? | 1) Control 2) Randomization 3) Replication | 29 | |
| 5176096950 | Replication | Using enough experimental units to distinguish a difference in the effects of the treatments from chance variation. | 30 | |
| 5176096951 | Placebo | Does not have an active ingredient...e.g. sugar pill | 31 | |
| 5176096952 | Placebo Effect | A fake treatment that results in subjects reporting a response expected from the real treatment | 32 | |
| 5176096953 | Double-Blind | Neither the subjects or those who interact with them and measure the response variable know which treament the subject received | 33 | |
| 5176096954 | Single Blind | One side is blind - either the subject or the researcher. The researchers taking measurements do not know if the subject is in the control or treatment group OR the subject does not know | 34 | |
| 5176096955 | Statistically Significant | An observed effect so large that it would rarely occur by chance | 35 | |
| 5176096956 | Blocking | A form of control. Grouping similar experimental units together that are know before the experiment to be similar in some way and expected to affect the response to treatments | 36 | |
| 5176096957 | Randomized Block Design | Reduces the effect of variation among experimental units. e.g. separate laundry into white and color then randomly assign 1/2 of each block to be washed in hot or cold water. | 37 | |
| 5176096958 | Matched Pairs Design | A common type of randomized block design for comparing 2 treatments. In some matched pairs design, each subject receives both treatments in a random order. In others, subjects are matched up in pairs as closely as possible and each subject in the pair receives one of the treatments. | 38 |
