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| 7796915117 | What is the population in a statistical study? | the entire group of individuals about which we want information | 0 | |
| 7796915118 | What is the sample in a statistical study? | part of the population from which we actually collect information. We use this to draw conclusions about the entire population. | 1 | |
| 7796915119 | What is a convenience sample, and why is it not a good technique? | choosing individuals who are easiest to reach results. However, it creates a bias, because it will consistently overestimate or underestimate the value that you want to know | 2 | |
| 7796915120 | What is a bias? | design of a statistical study that systematically favors certain outcomes | 3 | |
| 7796915121 | What is a voluntary response sample, and why is it not a good technique? | consists of people who choose themselves by responding to a general appeal. It creates a bias because people with strong opinions (often in the same direction) are most likely to respond | 4 | |
| 7796915122 | What is random sampling? | the use of chance to select a sample, is the central of statistical sampling | 5 | |
| 7796915123 | What is a simple random sample (SRS)? | every individual from the population has an equal chance to be selected in the sample. You can use a table of random digits to generate random numbers | 6 | |
| 7796915124 | What is the problem with SRS? | it is difficult getting an SRS from the whole population of interest and time-consuming | 7 | |
| 7796915125 | How do you conduct a stratified random sample? | first classify the population into strata (groups of similar individuals). Then choose a separate SRS in each stratum and combine these SRSs to form the full sample. | 8 | |
| 7796915126 | How do you choose groups/strata in a stratified random sample? | based on facts known before the sample is taken. | 9 | |
| 7796915127 | What is the problem with a stratified random sample? | it is difficult to conduct when the populations are large and spread out over a wide area | 10 | |
| 7796915128 | How do you conduct a cluster sample? | first divide the population into smaller groups (clusters) that ideally mimic characteristics of the population. Then choose an SRS of the clusters. All individuals in the chosen clusters are included in the sample. | 11 | |
| 7796915129 | What are multistage samples? | they combine two or more sampling methods. | 12 | |
| 7796915130 | What is an inference? | what we predict information about the population from what we know about the sample | 13 | |
| 7796915131 | What is a sampling frame? | the sampling list; list of individuals from which we will draw our sample | 14 | |
| 7796915132 | What is undercoverage? | when some groups in the population are left out of the process of choosing the sample, leaving some bias | 15 | |
| 7796915133 | What is a nonresponse bias? | when a selected individuals cannot be contacted or refuses to cooperate | 16 | |
| 7796915134 | What is response bias? | when someone gives an incorrect response on purpose | 17 | |
| 7796915135 | What is the wording of questions bias? | confusing or leading questions can introduce a strong bias, and changes in wording can greatly change a survey's outcome. | 18 | |
| 7796915136 | What is an observational study? | observes individuals and measures variables of interest but does not attempt to influence the responses | 19 | |
| 7796915137 | What is an experiment? | deliberately imposes some treatment on individuals to measure their responses. These are the only source of fully convincing data and to understand cause and effect. We actually impose treatment to the experimental units to observe the response. | 20 | |
| 7796915138 | What is a confounding variable? | when two variables are associated in such a way that their effects on a response variable cannot be distinguished from another | 21 | |
| 7796915139 | What are factors in an experiment? | the explanatory variables in an experiment | 22 | |
| 7796915140 | What is random assignment? | in an experiment, experimental units are assigned to treatments at random using some sort of chance process | 23 | |
| 7796915141 | What is a completely randomized design? | the treatments are assigned to all the experimental units completely by chance. | 24 | |
| 7796915142 | Example of completely randomized design outline: | -state the random assignment -state the sizes of groups -which treatments the groups receive -the response variable |  | 25 |
| 7796915143 | What is the purpose of a control group? | provide a baseline for comparing the effects of the other treatments | 26 | |
| 7796915144 | What are the three principles of experimental design? | -a proper comparative design ensures that influences other than the experimental treatments operate equally on all groups. (CONTROL) -random assignment helps balance out the effects of lurking variables. (RANDOM ASSIGNMENT) -since the groups are roughly equivalent except for the treatments, any differences in average response must be due either to the treatments or to the play of chance in the random assignment of experimental units to the treatments. (REPLICATION) | 27 | |
| 7796915145 | What is the placebo effect? | response to a dummy treatment | 28 | |
| 7796915146 | What is double-blind? | neither the subjects nor those who interact with them and measure the response variable which treatment a subject received | 29 | |
| 7796915147 | What does it mean to be statistically significant? | an observed effect so large that it would rarely occur by chance. Implies causation | 30 | |
| 7796915148 | Example of a randomized block design outline: | -experimental units are first separated into blocks to deal with the potential confounding variable -each block will be randomly assigned to both treatments |  | 31 |
| 7796915149 | What is a block in a randomized block design? | group of experimental units that are known before the experiment to be similar in some way that is expected to affect the response to the treatments. It is another form of control. | 32 | |
| 7796915150 | What is a matched pairs design? | common type of randomized block design for comparing two treatments. You create blocks by matching pairs of similar experimental units. Then we use chance to decide which members get which treatments. | 33 | |
| 7796915151 | What is lack of realism? | treatments, subjects, or environments of our experiment may not be realistic. It limits our ability to apply the conclusions of an experiment to the settings of greatest interest | 34 | |
| 7796915152 | What are the criteria for establishing causation when we can't do it an experiment? | -association is strong -association is consistent -larger values of explanatory variable are associated with stronger responses -alleged cause precedes the effect in time -alleged cause is plausible | 35 |
