Research Methods Flashcards

1
Q

What are the 3 Steps in the Statistical Process?

A

1) Collect Data
2) Describe & Summarize the Distribution
3) Interpret - draw general conclusion for the pop on the basis of the sample

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2
Q

What is Nominal Data?

A

Mutually Exclusive groups, lack intrinsic order.

Zoning classification, social security numbers, sex.

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3
Q

What is Ordinal Data?

A

Ordered implying a ranking of observations. Values are meaningless - rank is important.

Letter grades, response scales on a survey 1-5, suitability for development

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4
Q

What is Interval data?

A

Data with ordered relationship where the difference between scales has meaning.

Temperature. Diff between 40 and 30 degrees is the same as 30 and 20 but 20 degrees is not twice as cold as 40 degrees.

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5
Q

What is Ratio Data?

A

Gold standard of measurement. Absolute and relative difference have meaning.

Distance measurement. 40 - 30 miles is the same difference as 30-20 miles and 40 miles is twice as far as 20 miles.

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6
Q

What are Quantitative Variables?

A

Variables where numerical value is meaningful.

Interval or ratio measurement.

Household income, level of pollution in river

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7
Q

What are Qualitative Variables?

A

Variables where numerical value is not meaningful.

Nominal/Ordinal measurement.

Zoning classification

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8
Q

What are Continuous Variables?

A

Infinite number of values.

Positive & negative.

Most measurements in physical sciences yield continuous variables.

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9
Q

What are Discrete variables?

A

Finite number of distinct values.

Accidents per month - can’t be negative.

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10
Q

What are Binary/dichotomous variables?

A

Special case of discrete variables which can only take on two values - 0/1 typically.

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11
Q

What are Descriptive variables?

A

Describe the characteristics of the distribution of values in a population or sample.

Ex: on average, AICP test takers in 2018 are 30 years old

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12
Q

What are Inferential Statistics?

A

Using probability to determine characteristics of a pop based on a sample.

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13
Q

Define Distribution

A

The overall shape of observed data.

Ordered table, or histogram, or density plot

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14
Q

What is the Normal or Gaussian Distribution?

A

the bell curve.

Distribution is symmetric. The spread around the mean can be related to the proportion of observations.

More specifically, 95% of the observations that follow a normal distribution are within two standard deviations from the mean

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15
Q

What is the Symmetric distribution?

A

equal number of observations are below and above the mean

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16
Q

What is a Central tendency?

A

Typical or representative value for the distribution of observed values

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17
Q

What is the Coefficient of Variation?

A

the relative dispersion from the mean by taking the standard deviation and dividing by the mean.

18
Q

What is a z-score?

A

This is a standardization of the original variable by subtracting the mean and dividing by the standard deviation.

The z-score in effect transforms the original measure into standard deviation units.

19
Q

What is the inter-quartile range or IQR.?

A

Alternative measure of dispersion.

Breaks things into quartiles.

This is visualized in a box plot (also called box and whiskers plot).

20
Q

What is the confidence interval?

A

this constitutes a range around the sample statistic that contains the population statistic with a given level of confidence, typically 95% or 99%.

21
Q

Define Standard Deviation

A

A measure of how much the data in a certain collection are scattered around the mean. A low standard deviation means that the data are tightly clustered; a high standard deviation means that they are widely scattered. There are two common formulas used for standard deviation, both yielding the same result.

22
Q

Define Variance

A

The square of the standard deviation. It is a mathematical expectation of the average squared deviations from the mean. The formula is the same as that for the standard deviation except the “s” variable is squared, and no square root function is performed.

23
Q

What is a t-test?

A

allows us to compare the means of two groups and determine how likely the difference between the two means occurred by chance.

24
Q

What is the correlated t-test?

A

concerned with the difference between the average scores of a single sample of individuals who is assessed at two different times (“before” vs. “after”) or on two different measures. The measures must be correlated (co-related), and so it can also compare average scores of samples of individuals who are paired in some way (i.e. parent-child).

25
Q

What is an ANOVA and what does it stand for?

A

An extension of the t-test. It stands for Analysis of Variance. It allows a composite view of data by assuming that by placing variable x into groups, a better understanding of variable y will be found.
o ANOVA identifies the relationship between two variables.
o The x variable is always nominal
o The y variable is always interval
* Mathematically, a line is expressed as y = Mx + b

25
Q

What is the independent t-test?

A

compares the averages of two samples that are selected independently of each other. Independent t-tests come in “equal variance” and “unequal variance” flavors, but these go beyond the scope of this work.

26
Q

Define Correlation

A

measures the strength of the relationship between variables or the degree to which two variables are correlated (co-related). It is used to demonstrate relationships between situations and/or actors, even disparate ones (think apples and oranges). The test is linear.

27
Q

Define Regression

A

a statistical test of the effect one variable (condition/actor) has on another while holding all other conditions constant. This test is also linear. If there is no correlation, there is no need to utilize a regression test. Regression allows us to predict the value of one variable give the value of the other, or explore the relationships between variables.
o There is always one dependent variable (y) in regression.
o In simple regression, there is only one independent variable. The formula for simple regression is y=b0+b1x1.
o In multiple regression, there are two or more independent variables. Multiple regression simply extends simple regression y=b0+b1x1.+b2x2+ … bnxn.
o Regression answers one or more of these questions:
. What is the association between x and y?
. How can changes in y be explained by changes in x?
. What are the functional relationships between y and x?
o Beware of false relationships! Correlation and regression can be used to “prove” that fire trucks cause house fires (if there is a house fire, there are likely fire trucks).

28
Q

A properly selected statistical sample of a large population will always?

A

A) Reduce the amount of effort required to ascertain characteristics of the population.
B) Provide a mathematical estimate of the accuracy of the calculated population
characteristics.
C) Be the unbiased sample of the entire population.
D) Be of adequate size to satisfy confidence criteria if a pre-sample was used to
determine the required sample size.

The correct answer is “B”.

29
Q

What is the range of the numbers 5, 10, 20, 30?

A

A) 5
B) 10
C) 25
D) 30

The correct answer is C)

30
Q

An age group in the 85th percentile:

A

A) has 15% of the population below it
B) has 85% of the population below it
C) is in the interquartile range
D) is in the median range

The correct answer is B)
The 85th percentile of a set of individuals indicates that 85% of the individuals in the set
are younger.

31
Q

What is the variable x in the equation Y=(x)?

A

A) dependent variable
B) dependent sample
C) independent variable
D) function

The correct answer is C)
X is the independent variable; Y is the dependent variable.

32
Q

What are the two basic types of statistical groupings?

A

A) frequency and mode
B) ordinate and inordinate
C) quantitative and qualitative
D) X and Y

The correct answer is C)
Quantitative groups variables into ordered class intervals; qualitative groups variables
into disparate categories.

33
Q

What is a curve generated as the result of a quadratic equation called?

A

A) a parabola
B) a variable
C) discrete data
D) none of the above

The correct answer is A)
The equation of a parabola is: y=ax2+bx+c.

34
Q

The Department of Economic Opportunity wants to assess the quality of
comprehensive plans for the twelve largest counties in Florida before and after the
2011 legislative changes in state oversight of growth management. The technique
that would most likely be used is called:

A

A) Central tendency
B) Fournier Analysis
C) Meta-analysis
D) Monte-Carlo Method

The correct answer is C)
Meta-analysis is a powerful tool when used appropriately to provide valuable insights
into plan performance by making scores comparable across various plan quality
characteristics,

35
Q

Surveying by social media runs the risk of:

A

(A) Sampling error
(B) Sample bias
(C) Systematic bias
(D) Exclusion error

The correct answer is “B”

36
Q

Bias in statistics:

A

(A) Can be due to choosing random data for statistical analysis
(B) Can be minimized by increasing the size of the sample
(C) Can be caused by faulty design or deficient execution of the sampling process
(D) Is a consequence of the fact that sample size is much less when compared to the
population size

The correct answer is “C”

37
Q

What is the population project technique that allocates a projected population
expansion to subregional areas called?

A

A) demographic approach
B) input-output approach
C) shift-share approach
D) marketing approach

The correct answer is C)

38
Q

Location quotient equals which of the following?

A

A) the ratio of total local employment of an industry to that industry nationally
B) the ratio of total national employment of an industry to that industry locally
C) the ratio of total number of local industries to that industry nationally
D) the ratio of total number of national industries to that industry locally

The correct answer is A)
Location quotients are used to determine the ratio of total local employment of a specific
industry to that of the industry on a national basis.

39
Q

Which analysis would generate results indicating the community’s population
cohorts?

A

A) analysis of housing supply
B) analysis of housing demand
C) analysis of housing need
D) analysis of subsidy program availability

The correct answer is B)
Population statistics is a key component of an analysis of housing demand.

40
Q

The dissimilarity index:

A

(A) Measures the genetic diversity between two species used to determine whether
two species constitute one or two discrete species.
(B) Is a census-related term that measures the relative separation or integration of
groups across all neighborhoods of a city or metropolitan area
(C) Is a statistical term that measures the degree of separation between two data
sets
(D) Is the inverse of the correlation coefficient

The correct answer is “B”
The index of dissimilarity is a demographic measure of the evenness with which two
groups are distributed across component geographic areas that make up a larger area.
The index score can also be interpreted as the percentage of one of the two groups
included in the calculation that would have to move to different geographic areas in order
to produce a distribution that matches that of the larger area.

41
Q

What is the smallest census geographic unit with 100% tabulation of data?

A

(A) Consolidated MSA
(B) Census Tract
(C) Census Block
(D) Place

The correct answer is “C”