Chapter 1

Question 1

Research Design

Answer 1

planning and designing appropriate ways of collecting data for the
investigation of a particular scientific problem

Question 2

Descriptive Statistics

Answer 2

description, summarization and presentation of data using both numerical and graphical methods

Question 3

Inferential Statistics

Answer 3

drawing scientific conclusions and making a prediction ab population based on the data from a sample of the population. eg: hypothesis tests, confidence intervals, making a estimate ab population based on size of sample.

Question 4

Variable

Answer 4

any characteristic that varies (natural variation), often several, the “What”.

Question 5

Distribution of a Variable

Answer 5

all the values that a variable takes on.

Question 6

Categorical Variables (Qualitative Variable)

Answer 6

Data Recorded on a Nominal (names) Scale, is a non-numerical value. No measurements are obtained from this but they obtain numbers for analysis eg: color, gender, animals

Question 7

Nominal Scale (name scale)

Answer 7

Nominal scales may sometimes be assigned numbers for ease of recording, but the variable is still
categorical (not quantitative), for example, 1 = single, 2 = common-law, 3 = married, 4 = separated, 5 = widowed, 6 = divorced.

Question 8

Binary categorical variable

Answer 8

a variable that has only two possible categories

Question 9

Ordinal Scale Variables/Data

Answer 9

Data or observations can be put in order from lowest to highest, but which do not have a constant interval between successive units, i.e., the data can be ranked. an ordinal scale of 1 – 5 can be used, where 1 = very poor, 2 = poor, 3 = moderate, 4 = good, 5 =very good.

Question 10

Quantitative Variables/Data

Answer 10

A quantitative variable is a numerically-valued variable.
Constant interval size between successive units.

Question 11

Discrete or discontinuous quantitative variable

Answer 11

a quantitative variable whose possible values only take on specific values, usually whole numbers.
▪ a countable variable.
▪ e.g., the number of people, animals, or stars must be whole numbers.

Question 12

Continuous quantitative variable

Answer 12

a quantitative variable that has an infinite number of possible values between any observed range.
▪ a measureable variable.
▪ e.g., the weight of a person may be 71 kg or 72 kg or an infinite number of possible values
between, e.g., 71.42 kg or 71.42893 kg, depending upon the accuracy of the balance used.
▪ Time, distance and height (regardless of units) are always continuous variables.
▪ Even if the measurements are rounded to whole numbers

Question 13

Explanatory or Predictor variables

Answer 13

variables of interest that are hypothesized to explain or affect other variables in the study, but which are not likely to be affected by those other variables. (Independent Variable)

Question 14

Response variable

Answer 14

the variable that is hypothesized
to be affected by the explanatory or independent variables. (Dependant Variable)
* E.g., age and height – height does not affect age, but age affects height

Question 15

Extraneous variables

Answer 15

Explanatory variables that are NOT of interest or are NOT related to the purpose of the study, though they could be of interest in a different study.
* These may potentially affect the response variable, interfering with the study and leading to “experimental error”.

Question 16

Factors (Categorical predictor variables)

Answer 16

When explanatory variables are applied as treatments in an experiment or considered as levels in an observational study,
* The researcher tries to determine the effects that the different levels of the factor have on the responses of the study units

Question 17

Spatial Aspects of Design

Answer 17

The “Where” Involves the way the observations or replicates are arranged in space (distance, area, or volume), where they are sampled and measured

Question 18

Temporal Aspects of Design

Answer 18

The “When” Involves the way observations or replicates are arranged in time
* Time period (year, month, time of day) and frequency of observations
* Start, end, frequency of recording the variables

Question 19

Techniques and Methods of Data Collection

Answer 19

The “How”
* Specific methods and techniques used to take measurements of the variables or to record data

Question 20

Simple random sampling

Answer 20

o Every individual is selected completely randomly and independently
o Every group or area of the population have an equal chance of selection
o All the statistical tests dealt with in this course require simple random sampling

Question 21

Systematic random sampling

Answer 21

o The first sample is selected randomly, then all other samples are selected sequentially,
E.g., every 30 seconds of swimming over a coral reef, every 10 m, every 5 min, o E.g., every 5th person, etc.
o E.g. sampling plots in a forest
o Usually random enough unless there is a rhythmic cycle in the data

Question 22

Stratified random sampling

Answer 22

The population is divided into strata, based on a pilot study or some prior information
o Items within each subpopulation are considered relatively homogeneous
o Proportional allocation = sampling intensity in each stratum is proportional to the
estimated density of the items in the stratum or size of the stratum

Question 23

Multistage Random sampling

Answer 23

• Example of sampling leaves on trees of a certain species:
  o Randomly sample trees, then
  o Randomly sample the branches on the selected trees, then
  o Randomly sample some of the leaves from the selected branches and take them for
  analysis.

Question 24

Cluster Random Sampling

Answer 24

For example, if a company with a large number of apartment blocks (e.g. 100) want to get the
opinions of their tenants about some proposed changes.
▪ Randomly select a few apartment blocks and then interview all the tenants in the selected
blocks. Each selected block would then be considered as a cluster.

Question 25

Convenience sampling

Answer 25

selecting individuals for recording data simply because they are convenient to observe information from or question
* E.g. interviewing people in a shopping mall

Question 26

Voluntary response bias

Answer 26

asking for volunteers to participate in a social survey

Question 27

Response bias

Answer 27

questions in a social survey that appear to suggest or prompt a particular response favored by the researcher

Question 28

Nonresponse bias

Answer 28

occurs when a large fraction of those sampled fail to respond to some or any of the questions

Question 29

Incomplete sampling frame

Answer 29

some individuals or groups who actually belong to a certain population are not included in the sampling frame

Question 30

Undercoverage

Answer 30

some portion of the population not being included or given smaller representation

Question 31

Observational Research

Answer 31

IMPORTANT CHECK NOTES

Question 32

Experimental Studies

Answer 32

IMPORTANT CHECK NOTES

Question 33

Extraneous Variables

Answer 33

IMPORTANT CHECK NOTES

Question 34

Blinding

Answer 34

Those who could affect the results, and those who evaluate the results

Question 35

Single-blind experiment

Answer 35

all individuals of one or the other of the above groups are blind.

Question 36

Double Blind Experiment

Answer 36

all individuals of both of the above groups are blind.

Question 37

Placebo Effect

Answer 37

Psychological effect of receiving a placebo, which may result in a subject responding to a treatment when, in fact, they only received an inert placebo.