Class Notes

Question 1

Measurement

Answer 1

Measurement is the assignment of numbers to objects to reflect their possession/non-possession or degree of possession of a particular attribute.

Question 2

Ratio-level

Answer 2

 the assignment of numbers to objects to reflect absolute magnitude  the zero level is fixed and has meaning  ratio comparisons are permitted

Question 3

Interval-level

Answer 3

 the assignment of numbers to objects to reflect magnitudes in terms of differences between differences  zero level is not fixed  ratio comparisons are not permitted

Question 4

Ordinal-level

Answer 4

 the assignment of numbers to objects to reflect order  differences between differences may not be compared  ratio comparisons are not permitted

Question 5

Nominal-level

Answer 5

 the assignment of numbers to objects to serve as labels

Question 6

Population

Answer 6

definable set of entities that are finite and countable.

Question 7

Census

Answer 7

the recording of one or more characteristics for every member of a population

Question 8

Sample

Answer 8

a subset of a population.

Question 9

Random sample

Answer 9

a subset of a population chosen in such a way that every entity in the population possesses an equal chance of being selected.

Question 10

Stratified random sample

Answer 10

a subset of a population in which different segments have a predetermined number of elements, the number of elements typically corresponding to the size of that segment in the population. Each element within a particular segment has an equal chance of being selected.

Question 11

Systematic random sample

Answer 11

a subset of a population selected in the following manner: a starting point is chosen at random, then every xth element is selected. x=N/n. (N=population, n=sample size)

Question 12

Mean

Answer 12

Question 13

Average Deviation

Answer 13

Question 14

Variance

Answer 14

Question 15

Standard deviation

Answer 15

Question 16

Skewness

Answer 16

Question 17

Kurtosis

Answer 17

Question 18

Steps to determine if X and Y are related

Answer 18

Question 19

Steps to determine if X and Y are unrelated

Answer 19

Question 20

Scalar

Answer 20

A number

Question 21

Vector

Answer 21

A column of numbers

Question 22

Linear combination

Answer 22

A scalar times a vector plus a scalar times a vector,, plus a scalar times a vector . . . etc..

Question 23

Linear independence

Answer 23

A set of vectors is said to be linearly independent if no vector in the set can be expressed as a linear combination of others in the set..

Question 24

How to determine linear independence

Answer 24

Question 25

Calculate F

Answer 25

Question 26

Linear model

Answer 26

is a linear combination of a set of predictor vectors . It is a model in the sense that it is intended to reproduce (or fit)) the values for one variable (we call it the dependent variable)) given the values on one or more other variables (we call them the independent variables)).

Question 27

Full model vs restricted model

Answer 27

To test our hypotheses, we need to create two models --- a full model and a restricted model – and compare them in terms of their fit to a set of data. The restricted model is created by imposing a linear restriction on the weights in the full model. If the linear restriction is true, then the restricted model will fit the data almost as well as the full model. If the linear restriction is not true, then the restricted model will not fit the data as well as the full model.

Question 28

Error sum of square

Answer 28

The error sum-of-squares is a measure of how well our model "fits" the data.

Question 29

F Statistic

Answer 29

Question 30

Steps for a 1 independent variable test

Answer 30

Question 31

Raw values can be included in a regression model when...

Answer 31

variables can be included in a regression model with their original raw values only if they are measured at the interval or ratio level.

Question 32

Steps for developing a regression model

Answer 32

Question 33

Adjusted R-Square

Answer 33

Question 34

Standard Error of the Estimate

Answer 34

Question 35

t-statistic

Answer 35

the t-statistic is the ratio of the departure of the estimated value of a parameter from its hypothesized value to its standard error. It is used in hypothesis testing.

Question 36

p-value

Answer 36

When you perform a hypothesis test in statistics, a p-value helps you determine the significance of your results. ... The p-value is a number between 0 and 1 and interpreted in the following way: A small p-value (typically ≤ 0.05) indicates strong evidence against the null hypothesis, so you reject the null hypothesis.

Question 37

Correlation coefficient

Answer 37