Analysis and Interpretation of Statistical Data Flashcards
The four descriptive statistics
Central tendency, variability, symmetry, measures of position
Predictive statistics
Linear regression, multiple regression, stepwise regression, standardized regression coefficients
If you want to see the DIFFERENCE between or among groups, the family of statistical tests fall under this
Statistical tests for comparison
If you used RANDOM/PROBABILITY SAMPLING, you use what statistical test for comparison test
Parametric tests
If you used NON-PROBABILITY SAMPLING, you use what statistical test for comparison test
Non-parametric tests
Central tendency measure to use if your data is an INTERVAL/RATIO and is NOT SKEWED
Mean
Central tendency measure to use if your data is an INTERVAL/RATIO and is SKEWED
Median
Central tendency measure to use if your data is NOMINAL
Mode
Variability measure that gets the difference between the HIGHEST AND LOWEST SCORES
Range
Variability measure that gets the difference between the 75th and 25th PERCENTILE
Interquartile range
Variability measure that shows the DEGREE OF SPREAD within the distribution
Variance
Variability measure that shows the DISTANCE FROM THE MEAN
Standard Deviation
This helps interpreting measures of central tendency
Measures of symmetry
The pattern of a positively skewed data
mean > median > mode
The pattern of a negatively skewed data
mean
Under measures of symmetry, this shows the LACK OF SYMMETRY OF DATA
Skewness
These are DEVELOPMENTAL NORMS under the measures of position
Age norms/comparison and grade equivalents
The formula for z-test
n - mean/SD
The percent of people FALLING BELOW the obtained percentile
Percentile score
Linear transformation: we use this formula to convert a z score to a different standardized score like t-test, stanine, deviation IQ or vice versa
SD (z) + mean
The standardized score usually used for PERSONALITY TESTS
t-test
The standardized score usually used for ACHIEVEMENT TESTS
Stanine
Mean and SD of Stanine
M = 5; SD = 2
The standardized score usually used for PERSONALITY INVENTORIES AND QUESTIONNAIRES
Sten
Mean and SD of Sten
M = 5.5; SD = 2
The standardized score usually used for INTELLIGENCE TESTS
Deviation IQ
Mean and SD of Dev IQ
M = 100; SD =15
The standardized score usually used for EDUCATIONAL TESTS
Normal Curve Equivalents (NCEs) scores
Mean and SD of Normal Curve Equivalents scores
M = 50; SD = 21.06
Mean and SD of SATs and GREs (scholastic aptitude test, graduate record exam)
M = 500 SD = 100
In a NORMAL DISTRIBUTION the mean, median, and mode have
The same value
The % of people falling under -1 AND +1 in a normal curve
68.26%
The % of people falling under +1 or -1 part of a normal curve
34.13%
The % of people falling under -2 AND +2 in a normal curve
95.50%
The % of people falling under +2 or -2 part of a normal curve
13.59%
The % of people falling under -3 AND +3 in a normal curve
99.75%
The % of people falling under +3 or -3 part of a normal curve
2.15%
Under inferential statistics, this is a random interval (AKA confidence interval) in which the true value of the parameter falls with some level of probability
Interval estimate
For the confidence interval, the ____ the confidence level, the ____ the CI
Higher, wider
The alpha of a confidence interval with 90%
.05
The alpha of a confidence interval with 95%
.025
The alpha of a confidence interval with 99%
.005
The alpha of .05 is equal to what z-score
1.65
The alpha of .025 is equal to what z-score
1.96
The alpha of .005 is equal to what z-score
2.58
In the critical value approach of hypothesis testing, if value of test stat FALLS WITHIN the critical region, what do we do with H0/null?
Reject
In the critical value approach of hypothesis testing, if value of test stat DOES NOT FALL WITHIN the critical region, what do we do with H0/null?
Do not reject
Guys, we don’t accept a null hypothesis, reject or not reject lang, OK?
In the P-value approach of hypothesis testing, if P-value less than or equal to the α/alpha, we ____ the H0/null
Reject
In the P-value approach of hypothesis testing, if P-value greater the α/alpha, we ____ the H0/null
Do not reject
Type I error or False ____, What did you to the null?
Positive; Did not reject, when you should have
Type I error or False ____, What did you to the null?
Negative; Rejected, but shouldn’t have
Akala mo lang wala! Pero meron!
These letters/symbols are used when pertaining to the POPULATION
Greek symbols
These letters/symbols are used when pertaining to the SAMPLE
Roman letters
A parameter has the symbol of
µ (mu)
A mean uses the letter
x
The SD of a population uses the symbol
σ (sigma)
The variance of a population uses the symbol
σ2
The variance of a sample uses
S2 (S squared yan ayaw lang mag-superscript ng Brainscape)
Your percentile you have a z-score of 1
84th percentile
A percentile of 84.1 means
84 people scored lower than you and you ranked 16th in a group
Your percentile you have a z-score of 2
98th percentile
A percentile of 98 means
98 people scored lower than you and you ranked 2nd in a group
Your percentile you have a z-score of 3
99th percentile
A percentile of 99 means
99 people scored lower than you and you ranked 1st in a group
Your percentile you have a z-score of -1
16th percentile
A percentile of 16 means
16 people scored lower than you and you ranked 84 in a group
Your percentile you have a z-score of -2
2nd percentile
A percentile of 2 means
2 people scored lower than you and you ranked 98 in a group
Your percentile you have a z-score of -3
1st percentile
A percentile of 1 means
1 person scored lower than you and you ranked 99 in a group
Meaningful transformation of raw scores
Standard scores
