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Statistics Lesson 2
Stats Quiz 5/29
Question | Answer |
---|---|
Cross-sectional study | data collected at a fixed point in time |
Retrospective (case controlled) study | data collected about the past (records, interviews, etc) |
Prospective study | data collected in the future from groups sharing common factors |
Randomization | Randomly select subjects for different groups |
Replication | Results can be repeated on more than one subject to reach the same result |
Blinding | Subjects do not know which group they are in (placebo) |
Double blinding | Researcher doesn't know which group the subject is in |
Placebo effect | An untreated subject reports and improvement in symptoms |
Confounding | occurs in an experiment when you are unable to distinguish the effects of different factors |
Completely Randomized Experimental Design | Assign subjects to different treatment groups through random selection |
Randomized Block Design | Form blocks of subjects with similar characteristics Randomly assign subjects within the blocks |
Rigorously Controlled Design | Carefully assign subjects to different treatments so that subjects for a particular treatment are important to the researcher. |
Matched Pairs Design | Compare exactly two treatment groups with subjects that are matched to have similar characteristics |
Sampling error | Results do not match results in whole population |
Nonsampling error | Occurs when data is incorrectly collected or analyzed |
Center | representative value for “the middle” of the data set |
Variation | measure of the amount of data that values vary |
Distribution | shape of the spread of the data |
Outliers | Sample values that lie far away from the majority of other values |
Frequency Distribution | also known as a frequency table, it shows how the data set is partitioned over various categories given by listing the categories and the number of data values in each category |
Lower-class limits | Smallest numbers that can belong to different classes |
Upper-class limits | Largest numbers that can belong to different classes |
Class boundaries | Centers in the gaps between upper and lower class limits of successive classes |