Chemical Engineering 426
Spring, 1997
B. Bernstein, Instructor
Assignment 1

 
Book:Vardeman, S. B. Statistics for Engineering 
Problem Solving

		PWS Publishing, Boston 114, ISBN 
0-534-92781-4

Read:Sections 1-1, 1-2, 1-3, 1-4, 2-1, 2-2, 2-3

Problems:page 20 # 1, 4, 7, 9, 15, 19; 
page 54 #2, 4, 6, 7, 8

Spring, 1997Chemical Engineering 426, Assignment 1page The following terms figure importantly in our subject:

observation study

Investigator is passive

experimental study

Investigator is active

population

Entire set of objects about which a statistical study is being made.

sample

A subset of the population on which data are taken.

enumerative study

Study on a well defined fixed population.

analytical study

Sampling at a particular place and/or time from a more fluid population.

quantative data

non-numerical data, e.g. blue eyes, green eyes.

quantitave data

numerical data, e.g. thickness of a plate.

Univariate data

one variable measured

multivariate data

several variables measured. For { bivariate data there are two variables measured, say thickness and area of a plate.

complete factorial study

All possible combinations of all controlled conditions of interest occur.

fractional factorial study

Only some of the possible combinations of controlled conditions of interest occur.

hierarchical (nested) study

There are sublevels of each level of controlled conditions.

accurate data

produces a correct value on average.

precise data

measured values of the variables are close to each other.

mathematical model

(of a situation) - a quantitative mathematical scheme for describing and doing calculations on the situation.

repeatability

A single operator can repeat measurements and get similar results each time.

reprocibility

Different operators get similar results.

random sample

A selection of objects in which each is equally likely to occur. (This definition may be modified later to consider selection according to some probability distribution)

Table of Random Numbers

See Table 2-2. page 30.

Supervised Variable

One which is chosen by the operator. These include controlled variables, which take a single value and experimental variables, which are given several settings.

response variable

One of primary interest.

concomitant variable

Observed, but not of primary interest.

randomization

A process to get rid of bias in choosing values of a variable.

replication

Doing experiment several times.

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