W7: Data Analysis I

Question 1

What are the steps of the research process?

Answer 1

1. Identify topic of interest
2. gather background info and ensure access
3. set research question(s)
4. choose design and methodology
5. develop tools and methods
6. access sample: begin data collection
7. Organize and analyze data
8. Interpret your results; define conclusions
9. Transfer knowledge

Question 2

What are the different types of statistics?

Answer 2

1. Descriptive
2. Inferential

Question 3

Define descriptive stats. Give an example

Answer 3

procedures/tools for describing individual variables, relationships between variables
eg. describing characteristics of study sample (sex, age, etc.; often table 1 in articles)

Question 4

Define inferential stats and give an example.

Answer 4

procedures used to analyze data after experiment is done & determine if an IV has significant effect; allow extrapolations from sample to population
eg. between group design

Question 5

What are the 3 levels of measurement? (descriptive)

Answer 5

• nominal
  -ordinal
  -ratio

Question 6

Define nominal and give an example.

Answer 6

numeric values are arbitrary, not ordered
eg. gender, political affiliation

Question 7

Define ordinal and give an example.

Answer 7

has continuum, values are ordered but intervals are not equal.
eg. Likert items, income brackets

Question 8

Define ratio and give an example.

Answer 8

numeric values assigned reflect equal intervals; has true zero
eg. weight, age in years

Question 9

Define Tendency and list the types

Answer 9

simple stats that typify set of values
- mean
-median
-mode

Question 10

When is mean used?

Answer 10

for describing ratio data
- aka arithmetic mean/average

Question 11

When is median used?

Answer 11

for describing ratio and ordinal

Question 12

When is mode used?

Answer 12

for describing ratio, ordinal, and nominal data

Question 13

What are measures of dispersion and what are the types?

Answer 13

describes variability of measures
- range
- standard deviation
- variance

Question 14

What is range? What kind of data is it used for?

Answer 14

calculated by subtracting lowest form highest value in set of values/ indicating lowest and highest values
(for ordinal and ratio data)

Question 15

What is standard deviation (SD)? What kind of data is it used for? What is it related to?

Answer 15

measure reflecting the average amount of deviation from meal value in set of values
(ratio level data)
related to normal distribution curve

Question 16

What is variance? How is it calculated? What kind of data is it used for?

Answer 16

single number that represents total amount of variation in distribution
variance = SD squared
(ratio level data)

Question 17

What is the purpose of standardizing data? Give an example.

Answer 17

allow for comparisons between units of different sizes.
eg. suicide rates
9.9/100,000 - Ontario
32.4/100,000- Northwest territories

Question 18

What are the 5 types of standardizing data?

Answer 18

• proportions
  -percentages
  -percentage change
  -rates
  -ratios

Question 19

Define proportions. What can it substitute? How is it calculated?

Answer 19

standard method of designating portion of total; ranges from .00 (none of total) to 1.00 (all of total)
- can be used instead of percentages
- batting average (BA)
BA= # of hits/# at bats

Question 20

what is a percentage?

Answer 20

proportion may be converted to % by multiplying by 100; denotes probability- how often something happens per 100 times

Question 21

What is percentage change? How is it calculated?

Answer 21

measure of how much something has changed over given time period.
(time 2-time1/time 1) x 100

Question 22

Define rates. Give an example.

Answer 22

represent frequency of something for a standard sized unit.
eg. divorce, suicide, crime

Question 23

Define ratios

Answer 23

represent comparison of one thing to another

Question 24

what is normal distribution?

Answer 24

aka normal curve/bell curve; based on concept: as number of scored in sample increases, scores approximate more so a “normal distribution”
half scores above and half below mean

Question 25

What characterizes a normal distribution (ND)?

Answer 25

mean, median, mode are same
distances from meal of a normal distribution can be measured in SD units
2/3 of cases +/- SD of mean (by definition)
(68.2% of scored in ND)

Question 26

Define Z-score

Answer 26

standardized score; represents distance above/below mean, in SD units, of any raw value in a distribution

usually range from +3 to -3 in value

Question 27

What are the different types of relationship between variables?

Answer 27

• cross tabular analysis
• comparison of means
• correlations

Question 28

What is cross tabular analysis. What kind of data is it used for?

Answer 28

used with nominal DV
data is cross- classified (sort into categories within IV and DV) to show relation between IV and DV

Question 29

when is comparing means used? What is its purpose? What tests of significance may be used for comparison of means?

Answer 29

when DV is ratio level data and when IV is either nominal/ordinal
- compare mean values of DV for each category of IV
- t-tests and ANOVA (test of sig.)

Question 30

When is correlation used (kind of data)? What is its purpose?

Answer 30

used to describe relationship between ratio level variables

describe how closely 2 ratio level variables co-vary together
(correlational analysis, correlational techniques)

Question 31

What are the two basic questions asked of the correlation?

Answer 31

1. what is the equation that describes relation between 2 variables?
2. What is the strength of the relation between 2 variables?

Question 32

What is the general equation for correlation?

Answer 32

Y= a +bX
estimates how much IV has to change in order to produce a unit of change in DV

Question 33

What is a regression line?

Answer 33

line that offers best linear description of the relation between 2 variables

Question 34

What is the correlation coefficient, r?

Answer 34

symbol used to report strength of correlation between 2 variables
can vary from -1.0 to +1.0

Question 35

What is the meaning of r= -1.0?

Answer 35

perfect negative correlation- negative slope; increase of 1 unit in 1 variable is associated with proportional decrease in other variable

Question 36

What is the meaning of r= +1.0

Answer 36

perfect positive correlation; positive slope