Quick Recap: Statistics

Question 1

Engineering Method

Answer 1

1. Develop a clear description
2. Identify the Important factors
3. Conduct Experiments
4. Propose or refine a model
5. Manipulate the Model
6. Confirm the Solution
7. Conclusions and Recommendations

Question 2

is the science of collecting, organizing, presenting, analyzing and interpreting numerical data to assist in making more effective decisions

Answer 2

statistics

Question 2

is a collection of all possible individuals, objects, or measurement of interest

Answer 2

population

Question 3

is a portion or part of the population of interest

Answer 3

sample

Question 4

the total number of things in the sample

Answer 4

sample size

Question 5

uses the data to provide descriptions of the population, either through numerical calculations or graphs or tables.

Answer 5

DESCRIPTIVE STATISTICS​

Question 6

makes inferences and predictions about a population based on a sample of data taken from the population in question.

Answer 6

INFERENTIAL STATISTICS

Question 7

Types of Variables

Answer 7

1. Qualitative/Categorical
2. Quantitative/numerical

Question 8

Variable with countable data

Answer 8

Discrete Variable

Question 9

Types of Quantitative Variable

Answer 9

1. Discrete
2. Continuous

Question 10

Measurable data, Intervals between whole numbers

Answer 10

Continuous Variable

Question 11

result when a single variable is measured on an experimental unit.

Answer 11

Univariate Data

Question 12

result when two variables are measured on a single experimental unit.

Answer 12

Bivariate data

Question 13

result when more than two variables are measured

Answer 13

Multivariate data

Question 14

General Types of Collecting Data

Answer 14

1. Retrospective Study using Historical Data
2. Observational Study
3. Designed Experiments

Question 15

This type of study strictly uses historical data, data taken over a specific period of time. In most cases, this type of study will be the least expensive. However, there are clear disadvantages:
(i) Validity and reliability of historical data are often in doubt.
(ii) If time is an important aspect of the structure of the data, there may be data missing.
(iii) There may be errors in collection of the data that are not known.
(iv) There is no control on the ranges of the measured variables (the factors in a study). Indeed, the ranges found in historical data may not be relevant current studies

Answer 15

RETROSPECTIVE STUDIES

Question 16

Observing the process or the population, disturbing it as little as possible, and records the quantities of interest.

Answer 16

OBSERVATIONAL STUDIES

Question 17

Deliberate or purposeful changes are made in the controllable variables in the system or process, observes the resulting system output data, and then makes inferences about which variables are responsible for the observed changes in output performance

Answer 17

DESIGNED EXPERIMENTS