MEASURES OF CENTRAL MEASURES OF CENTRAL TENDENCYTENDENCY

1. Mean1. Mean

2. Median2. Median

3. Mode3. Mode

CHARACTERISTICS OF MEANCHARACTERISTICS OF MEAN

• Measure of averageMeasure of average

• Influence by extremeInfluence by extreme scores (especially if scores (especially if distribution is small)distribution is small)

• Interval or ratio data Interval or ratio data

CHARACTERISTICS OF MEDIANCHARACTERISTICS OF MEDIAN

• Measure of positionMeasure of position

• NotNot influenced by extreme scores influenced by extreme scores • Ordinal or interval dataOrdinal or interval data

CHARACTERISTICS OF MODECHARACTERISTICS OF MODE

• Measure of frequencyMeasure of frequency

• NotNot influence by extreme influence by extreme ScoresScores

• Nominal DataNominal Data

Would you accept an education position Would you accept an education position Smart High School where the average Smart High School where the average salary is $74,200?salary is $74,200?

Would you accept an education position Would you accept an education position Smart High School where the average Smart High School where the average salary is $74,200?salary is $74,200?

TEACHER A: $100,000TEACHER A: $100,000TEACHER B: $95,000TEACHER B: $95,000TEACHER C: $90,000TEACHER C: $90,000TEACHER D: $85,000TEACHER D: $85,000TEACHER E: $1,000TEACHER E: $1,000****

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MEASURES OF VARIABILITY EXAMPLEMEASURES OF VARIABILITY EXAMPLE

GROUP A: 86.00 84.00 83.00 82.00 80.00GROUP A: 86.00 84.00 83.00 82.00 80.00

GROUP B: 95.00 90.00 90.00 75.00 65.00GROUP B: 95.00 90.00 90.00 75.00 65.00

MEASURES OF VARIABILITYMEASURES OF VARIABILITY

1. Range1. Range

2. Quartile Deviation2. Quartile Deviation

3. Mean Deviation3. Mean Deviation

4. Standard Deviation4. Standard Deviation

CHARACTERISTICS OF RANGECHARACTERISTICS OF RANGE

• Measure of distance between high Measure of distance between high high score and low score high score and low score • Indicates nothing about Indicates nothing about variability of scores between variability of scores between extreme scores extreme scores

• Does not consider all scores Does not consider all scores

CHARACTERISTICS OF QUARTILE CHARACTERISTICS OF QUARTILE DEVIATIONDEVIATION

• Measure of middle 50.00% of scores Measure of middle 50.00% of scores

• Quartile deviation is added to, Quartile deviation is added to, and subtracted from, medianand subtracted from, median

• Does not consider all scores Does not consider all scores

CHARACTERISTICS OF MEAN CHARACTERISTICS OF MEAN DEVIATIONDEVIATION

• Measure of middle 57.50% of scores Measure of middle 57.50% of scores • Mean deviation is added to, and Mean deviation is added to, and subtracted from, meansubtracted from, mean

• Considers all scores, but not Considers all scores, but not mathematically sound. mathematically sound.

CHARACTERISTICS OF STANDARD CHARACTERISTICS OF STANDARD DEVIATIONDEVIATION

• MEASURE OF VARIATIONMEASURE OF VARIATION AROUND MEANAROUND MEAN

• A RELATIVELY SMALL SD A RELATIVELY SMALL SD INDICATES LITTLE VARIABILITY. INDICATES LITTLE VARIABILITY. A RELATIVELY LARGE SD A RELATIVELY LARGE SD INDICATES MUCH VARIABILITYINDICATES MUCH VARIABILITY

• CONSIDERS ALL SCORESCONSIDERS ALL SCORES

CORRELATIONAL TECHNIQUESCORRELATIONAL TECHNIQUES

1. PEARSON PRODUCT-MOMENT1. PEARSON PRODUCT-MOMENT CORRELATION CORRELATION

2. SPEARMAN RANK-ORDER 2. SPEARMAN RANK-ORDER CORRELATIONCORRELATION

CHARACTERISTICS OF CORRELATIONCHARACTERISTICS OF CORRELATION

• CORRELATION COEFFICIENTSCORRELATION COEFFICIENTS RANGE FROM +1.00 TO -1.00RANGE FROM +1.00 TO -1.00

• SIGN INDICATES TYPE OFSIGN INDICATES TYPE OF CORRELATION AND NUMBER CORRELATION AND NUMBER INDICATES DEGREE OF INDICATES DEGREE OF CORRELATION CORRELATION

• POSITIVE CORRELATION POSITIVE CORRELATION INDICATES A DIRECTINDICATES A DIRECT RELATIONSHIPRELATIONSHIP

• NEGATIVE CORRELATIONNEGATIVE CORRELATION INDICATES AN INVERSE INDICATES AN INVERSE RELATIONSHIPRELATIONSHIP

• CANNOTCANNOT INFER CAUSE-AND- INFER CAUSE-AND- EFFECT EFFECT

t-TEST t-TEST

1. t-TEST BETWEEN SAMPLE AND 1. t-TEST BETWEEN SAMPLE AND POPULATION MEAN POPULATION MEAN

2. INDEPENDENT t-TEST2. INDEPENDENT t-TEST

3. DEPENDENT t-TEST3. DEPENDENT t-TEST

t-TEST BETWEEN SAMPLE AND t-TEST BETWEEN SAMPLE AND POPULATION MEAN POPULATION MEAN

DESIGN SCHEMADESIGN SCHEMA

R TR TA1A1 O O

RR = RANDOM ASSIGNMENT = RANDOM ASSIGNMENT

T T = TREATMENT = TREATMENT

OO = OBSERVATION OR TEST = OBSERVATION OR TEST

ANALYSIS OF VARIANCE ANALYSIS OF VARIANCE

1. SIMPLE ANOVA1. SIMPLE ANOVA

2. FACTORIAL ANOVA2. FACTORIAL ANOVA

ONE-WAY ANOVA (THREE GROUPS)ONE-WAY ANOVA (THREE GROUPS)

DESIGN SCHEMADESIGN SCHEMA

TTA1A1 O O (00 HOURS PRACTICE)(00 HOURS PRACTICE)

R TR TA2A2 O O (05 HOURS PRACTICE)(05 HOURS PRACTICE)

TTA3A3 O O (10 HOURS PRACTICE)(10 HOURS PRACTICE)

TWO-WAY ANOVA (2 x 2)TWO-WAY ANOVA (2 x 2)

DESIGN SCHEMADESIGN SCHEMA

TTA1B1A1B1 O O (GROUP 01, MALES)(GROUP 01, MALES)

TTA1B2A1B2 O O (GROUP 01, FEMALES)(GROUP 01, FEMALES)

RR TTA2B1A2B1 O O (GROUP 02, MALES)(GROUP 02, MALES)

TTA2B2A2B2 O O (GROUP 02, FEMALES)(GROUP 02, FEMALES)

ANALYSIS OF VARIANCE WITH ANALYSIS OF VARIANCE WITH REPEATED MEASURESREPEATED MEASURES

1. ONE-WAY ANOVA WITH 1. ONE-WAY ANOVA WITH REPEATED MEASURESREPEATED MEASURES

2. TWO-WAY ANOVA WITH 2. TWO-WAY ANOVA WITH REPEATED MEASURESREPEATED MEASURES

TWO-WAY ANOVA WITH REPEATED TWO-WAY ANOVA WITH REPEATED MEASURES (2 x 4)MEASURES (2 x 4)

DESIGN SCHEMADESIGN SCHEMA

TTA1B1A1B1 O T O TA1B2 A1B2 O TO TA1B3 A1B3 O TO TA1B4 A1B4 OO

RR TTA2B1A2B1 O T O TA2B2 A2B2 O TO TA2B3 A2B3 O TO TA2B4 A2B4 OO