STATS Exam #1
ratio
"My daughter is four years old." The scale of measurement involved in this statement is
interval
"My roommate's IQ is 95." The scale of measurement involved in this statement is
ordinal
"My son just finished 3rd in the local marathon." The scale of measurement involved in this statement is
nominal
"Watch for me on the football field. I'll be wearing number 32." The scale of measurement involved in this statement is
Proportion
A decimal number between 0 and 1 that indicates a fraction of the total is called a
parameter
A number that describes a characteristic of a population of scores is called a
statistic
A number that describes a characteristic of a sample of scores is called a
quasi-independent variable
A researcher investigates whether there is a relationship between participating in athletics and GPA by comparing GPAs from 20 randomly selected athletes with those from 20 randomly selected nonathletes. The variable measuring participation in athletics is a(n)
true independent variable
A researcher investigates whether there is a relationship between type of background music being listened to and responses to a mood inventory by having 60 randomly selected participants complete the mood inventory, with 20 randomly assigned to each of three rooms. In one room classical music is played in the background, in another hard rock music, and in a third country music. The type of background music variable is a(n)
weird E
Adding numbers is an important procedure in statistics. Instead of saying "add up all of the scores," we use the symbol
percentiles are often easier to interpret than cumulative frequencies.
An advantage of percentiles over cumulative frequencies is that
data point
Each "dot" on a graph
2 diagonal lines
For any graph, whenever there is a large gap between 0 and the lowest score you are plotting, the axis is compressed using
8, 7, 6, 5, 4, 3, 2, 1
For the following data what values should be in the Score column of the frequency distribution table? 8, 8 8, 7, 5, 5, 5, 5, 4, 4, 3, 3, 3, 2, 1, 1, 1, 1, 1
Lp= (n+1)(p/100)
Formula for Location of Percentile
0.0005
If we convert the percentage 0.05% to a proportion, we get
the relative frequency of all scores between the two scores.
In a normal curve the proportion of the area under the curve between two scores represents
the scale of measurement being used and the shape of the distribution.
In order to decide which measure of central tendency is appropriate, you must first determine
true independent variable
Lighting condition, if controlled by the researcher, would be considered a(n)
location
Measures of central tendency are measures of
quasi-independent variable
Participants' income, categorized as "below poverty level" or "above poverty level," would be considered a(n)
f/N
Relative frequency formula
Sx=square root of E(x-mean)^2/N
Sample standard Deviation Formula
E(x-mean)^2/N
Sample variance formula
English letters; Greek letters
Statistics are represented by _____, and parameters are represented by _____.
statistical procedures
Statistics is a shortened version of
N
Symbol for the total number of scores in a study
quasi-independent variable
Technically, behavior-influencing variables that an experimenter cannot change by doing something to participants are called a(n)
mean of the sample.
The best predictor of an individual score in a sample of scores is the
participants
The individuals measured in a sample are called the
the distribution is symmetrical and the scale of measurement is interval or ratio.
The mean is the preferred measure of central tendency when
the point at or below which 50% of the scores fall.
The median is defined as
the scale of measurement is ordinal
The median is the preferred measure of central tendency when
nominal
The mode is the appropriate measure of central tendency when the scale of measurement is
relative frequency; percentile
The proportion of area under the normal curve that is directly above a score is the _____ of the score. The percentage of the normal curve to the left of a score is the _____ of the score.
f
The symbol for the number of times a score occurred.
individual differences
The term _____ refers to the fact that no two individuals are identical.
its value is divided by 10.
What happens to the mean of a distribution if every score is divided by 10?
independent variable
When deciding which type of graph (bar, line, histogram, etc.) is appropriate, we consider the characteristics of the
inflection points
Where the normal curve inflects, in between is %68 of scores.
histograms and frequency polygons
Which graphing techniques are appropriate for interval and ratio data?
the median
Which measure of central tendency is appropriate if the shape of the distribution is severely skewed?
ratio
Which measurement scale has a true zero?
nominal
Which measurement scale shows how one individual is qualitatively different from another?
nominal, ordinal, interval, ratio
Which of the following orders lists the scales of measurement from the scale that provides the least specific information to the scale that provides the most specific information?
negatively skewed
Which shape associates with mean<median<mode?
positively skewed
Which shape correlates with the data where mode<median<mean?
cumulative frequency
frequency of all scores @ or below a single score.
Area under part of the curve/total area under the curve
relative frequency represented in a normal curve
weird backwards u
the symbol for poplation mean
