STATISTICS

Question 1

the act of assigning numbers or symbols to characteristics of things according to rules

Answer 1

Measurement

Question 2

methods used to provide concise description of a collection of quantitative information

Answer 2

Descriptive Statistics

Question 3

method used to make inferences from observations of a small group of people known as sample to a larger group of individuals known as population

Answer 3

Inferential Statistics

Question 4

the property of “moreness”

Answer 4

Magnitude

Question 5

the difference between two points at any place on the scale has the same meaning as the difference between two other points that differ by the same number of scale units

Answer 5

Equal Intervals

Question 6

when nothing of the property being measured exists

Answer 6

Absolute 0

Question 7

a set of numbers who properties model empirical properties of the objects to which the numbers are assigned

Answer 7

Scale

Question 8

takes on any value within the range and the possible value within that range is infinite
- used to measure a variable which can theoretically be divided

Answer 8

Continuous Scale

Question 9

can be counted; has distinct, countable values
- used to measure a variable which cannot be theoretically be divided

Answer 9

Discrete Scale

Question 10

refers to the collective influence of all the factors on a test score or measurement beyond those specifically measured by the test or measurement

Degree to which the test score/measurement may be wrong, considering other factors like state of the testtaker, venue, test itself etc.

Measurement with continuous scale always involve with error

Answer 10

Error

Question 11

involve classification or categorization based on one or more distinguishing characteristics
- Label and categorize observations but do not make any quantitative distinctions between observations
- mode

Answer 11

Nominal

Question 12

rank ordering on some characteristics is also permissible
- median

Answer 12

Ordinal

Question 13

• contains equal intervals, has no absolute zero point (even negative values have interpretation to it)
• Zero value does not mean it represents non

Answer 13

Interval

Question 14

• has true zero point (if the score is zero, it means none/null)
• Easiest to manipulate

Answer 14

Ratio

Question 15

– defined as a set of test scores arrayed for recording or study

Answer 15

Distribution

Question 16

– straightforward, unmodified accounting of performance that is usually numerical

Answer 16

Raw Scores

Question 17

– all scores are listed alongside the number of times each score occurred

Answer 17

Frequency Distribution

Question 18

– being manipulated in the study

Answer 18

Independent Variable

Question 19

nonmanipulated variable to designate groups

Factor: for ANOVA

Answer 19

Quasi-Independent Variable

Question 20

– used in ANOVA to determine which mean differences are significantly different

Answer 20

Post-Hoc Tests

Question 21

allows the compute a single value that determines the minimum difference between treatment means that is necessary for significance

Answer 21

Tukey’s HSD test

Question 22

statistics that indicates the average or midmost score between the extreme scores in a distribution

Goal: Identify the most typical or representative of entire group

Answer 22

Measures of Central Tendency

Question 23

– the average of all the raw scores
- Equal to the sum of the observations divided by the number of observations
- Interval and ratio data (when normal distribution)
- Point of least squares
- Balance point for the distribution

Answer 23

Mean

Question 24

– the middle score of the distribution
- Ordinal, Interval, Ratio
- Useful in cases where relatively few scores fall at the high end of the distribution or relatively few scores fall at the low end of the distribution
- In other words, for extreme scores, use median (skewed)
- Identical for sample and population
- Also used when there has an unknown or undetermined score
- Used in “open-ended” categories (e.g., 5 or more, more than 8, at least 10)
- For ordinal data

Answer 24

Median

Question 25

– most frequently occurring score in the distribution

Answer 25

Mode

Question 26

if there are two scores that occur with highest frequency Not commonly used - Useful in analyses of qualitative or verbal nature - For nominal scales, discrete variables - Value of the mode gives an indication of the shape of the distribution as well as a measure of central tendency

Answer 26

Bimodal Distribution

Question 27

– an indication how scores in a distribution are scattered or dispersed

Answer 27

Variability

Question 28

statistics that describe the amount of variation in a distribution

Answer 28

Measures of Variability

Question 29

– equal to the difference between highest and the lowest score Provides a quick but gross description of the spread of scores When its value is based on extreme scores of the distribution, the resulting description of variation may be understated or overstated

Answer 29

Range

Question 30

dividing points between the four quarters in the distribution

Answer 30

Quartile

Question 31

refers to an interval

Answer 31

Quarter:

Question 32

measure of variability equal to the difference between Q3 and Q1

Answer 32

Interquartile Range:

Question 33

equal to the interquartile range divided by 2

Answer 33

Semi-interquartile Range:

Question 34

equal to the square root of the average squared deviations about the mean  Equal to the square root of the variance

Answer 34

Standard Deviation –

Question 35

equal to the arithmetic mean of the squares of the differences between the scores in a distribution and their mean Distance from the mean

Answer 35

Variance:

Question 36

– also known as Gaussian Curve Bell-shaped, smooth, mathematically defined curve that is highest at its center

Answer 36

Normal Curve

Question 37

_______ = approaches but never touches the axis

Answer 37

Asymptotically

Question 38

2 – 3 standard deviations above and below the mean

Answer 38

Tail

Question 39

right side of the graph is mirror image of the left side  Has only one mode and it is in the center of the distribution  Mean = median = mode

Answer 39

Symmetrical Distribution

Question 40

nature and extent to which symmetry is absent

Answer 40

Skewness

Question 41

few scores fall the high end of the distribution The exam is difficult More items that was easier would have been desirable in order to better discriminate at the lower end of the distribution of test scores

Answer 41

Positive Skewed

Question 42

when relatively few of the scores fall at the low end of the distribution  The exam is easy  More items of a higher level of difficulty would make it possible to better discriminate between scores at the upper end of the distribution

Answer 42

Negative Skewed

Question 43

____ is associated with abnormal, perhaps because the skewed distribution deviates from the symmetrical or so-called normal distribution

Answer 43

Skewed

Question 44

– steepness if a distribution in its center

Answer 44

Kurtosis

Question 45

relatively flat

Answer 45

Platykurtic

Question 46

relatively peaked

Answer 46

Leptokurtic

Question 47

somewhere in the middle

Answer 47

Mesokurtic

Question 48

high peak and fatter tails

Answer 48

High Kurtosis

Question 49

rounded peak and thinner tails

Answer 49

Lower Kurtosis

Question 50

raw score that has been converted from one scale to another scale

Answer 50

Standard Score

Question 51

– results from the conversion of a raw score into a number indicating how many SD units the raw score is below or above the mean of the distribution

Answer 51

Z-Scores

Question 52

– a scale with a mean set at 50 and a standard deviation set at 10

Answer 52

T-Scores

Question 53

a method of scaling test scores on a nine-point standard scale with a mean of five (5) and a standard deviation of two (2)

Answer 53

Stanine

Question 54

one that retains a direct numerical relationship to the original raw score

Answer 54

Linear Transformation

Question 55

– required when the data under consideration are not normally distributed

Answer 55

Nonlinear Transformation

Question 56

Normalizing the distribution involves stretching the skewed curve into the shape of a normal curve and creating a corresponding scale of standard scores, a scale that is technically referred to as _______________

Answer 56

Normalized Standard Score Scale

Question 57

standard to ten; divides a scale into 10 units

Answer 57

STEN

Question 58

– statistical method that uses a sample data to evaluate a hypothesis about a population

Answer 58

Hypothesis Testing

Question 59

– states there is a change, difference, or relationships

Answer 59

Alternative Hypothesis

Question 60

– no change, no difference, or no relationship

Answer 60

Null Hypothesis

Question 61

used to define concept of “very unlikely” in a hypothesis test

Answer 61

Alpha Level or Level of Significance

Question 62

– composed of extreme values that are very unlikely to be obtained if the null hypothesis is true

Answer 62

Critical Region

Question 63

If sample data fall in the critical region, the null hypothesis is _______

Answer 63

rejected