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Flashcards in Test #1 Deck (60)
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1

Statistics

- the study of how to collect, organize, analyze, and interpret numerical information from data
- both a science of uncertainty and the technology of extracting information from data

2

Individuals

the people or objects included in the study

3

Variable

a characteristic of the individual to be measured or observed

4

Quantitative Variable

has a value or numerical measurement for which operations such as addition or averaging make sense

5

Qualitative Variable

describes an individual by placing the individual into a category or group, such as male or female

6

Population data

the data from every individual of interest

7

Sample data

the data from some individuals or interest

8

Population Parameter

a numerical measure that describes an aspect of a population

9

Sample Statistic

a numerical measure that describes an aspect of a sample

10

Nominal level of measurement

- applies to data that consist of names, labels or categories
- no implied criteria by which the data can be ordered from smallest to largest

11

Ordinal level of measurement

- applies to data that can be arranged in order
- differences between data values either cannot be determined or are meaningless=

12

Interval level of measurement

- applies to data that can be arranged in order
- differences between values are meaningful

13

Ratio level of measurement

- applies to data that can be arranged in order
- both differences between data values and ratios of data values are meaningful
- the data has a true zero

14

Descriptive statistics

involves methods of organizing, picturing and summarizing information from samples or populations

15

Inferential statistics

involves methods of using information from a sample to draw conclusions regarding the population

16

Simple random sample

a subset of the population selected in such a manner that every sample size of n from the population has an equal chance of being selected

17

Four levels of measurement

1) Nominal
2) Ordinal
3) Interval
4) Ratio

18

Steps to draw a random sample

1) Number all members of the population sequentially
2) Use a table, calculator, or computer to select random numbers from the numbers assigned to the population members
3) Create the sample by using members with numbers corresponding to those randomly selected

19

Sampling Techniques

1) Random Sampling
2) Stratified Sampling
3) Systematic Sampling
4) Cluster Sampling
5) Multistage Sampling
6) Convenience Sampling

20

Random Sampling

Use a simple random sample from the entire population

21

Stratified Sampling

- Divide the entire population sequentially
- Strata are based on a specific characteristic such as age, income, education level, and so on
- All members of the stratum share the specific characteristic
- Draw random samples from each stratum

22

Systematic Sampling

- Number all members of the population sequentially
- from a starting point selected at random, include every kth member of the population sample

23

Cluster Sampling

- Divide the entire population into pre-exiting segments or clusters
- Clusters are often geographic
- Make a random selection of clusters
- Include every member of each selected cluster in the sample

24

Multistage Sampling

- Use a variety of sampling methods to crate successively smaller groups at each stage
- The final sample consists of clusters

25

Convenience Sampling

Create a sample by using data from population members that are already available

26

Census

measurements or observations from the entire population are used

27

Observational Study

observations and measurements of individuals are conducted in a way that doesn't change the response or the variable being measured

28

Experiment

a treatment is deliberately imposed on the individuals in order to observe a possible change in the response or variable being measured

29

Placebo Effect

occurs when a subject receives no treatment but (incorrectly) believes he or she is in fact receiving treatment and responds favorably

30

Completely randomized experiment

one in which a random process is used to assign each individual to one of the treatments