Welcome to the World of Statistics
ALBERTO A. RICO

32.01 – 40.00 - Very High
24.01 – 32.00 - High
16.01 – 24.00 - Average
8.01 – 16.00 - Low
0.00 – 8 .00 - Very Low

Problems of Prevailing Conditions
• What is the most prevalent career choices of Grade
12 students?
• What do the majority of population prefer to use to
replace plastic bags in the market?

Problems on Degree/Level/Extent
• What is the degree of student acceptance for the
implementation of the ROTC?
• What is the level of performance of Grade 10
students in an English test?
• What is the extent of the implementation of solid
waste management in the school from the lens of
college students?

Problems of Significant Difference
• Is there significant difference in the performance of
Sections A and B in the mathematics test?
• Are there a significant differences among the
performances of Sections A, B, C, D and E in the
mathematics test?
• Is there significant difference between the pretest and
post test scores of students in mathematics?
• Is there significant difference between the post test
results of the experimental and control groups?

Problems on Correlation
• What is the degree of correlation between Science
and Mathematics performance?
• What is the strength of correlation between Science
and Mathematics performance?
• Is there a significant correlation between Science and
Mathematics performance?

MEASURES OF CENTRAL TENDENCY
Mode Median Mean
Highest Frequency
Easiest to Determine
Most Unreliable
Less Affected by
Outliers
Determine Midpoint
Most Stable
Not Affected by
Outliers
Arrange Scores First
Add Scores/N
Most Reliable
Affected by Outliers
Known as Average

Measures of Variability
This is a summary statistic that
represents the amount of
dispersion in a data set.
Range = HS - LS

Measures of Relative Position (Descriptive)

Measures of Relative Position (Standardized)

• Stanine 1 = below -1.75;
• Stanine 2 = -1.75 to -1.25;
• Stanine 3 = -1.25 to -0.75;
• Stanine 4 = -0.75 to -0.25;
• Stanine 5 = -0.25 to 0.25;
• Stanine 6 = 0.25 to 0.75;
• Stanine 7 = 0.75 to 1.25;
• Stanine 8 = 1.25 to 1.75; and
• Stanine 9 = above 1.75.
Comparing Stanines with the ranges of z-score

Data Sets of 21 Students
in Grade 6 Math and
Science Tests
Problems:
1. What is the level of performance
of Grade 6 students in Math?
2. What is the level of performance
of Grade 6 students in Science?
3. Is there a significant difference
between the performance of
Grade 6 students in Science and
Math?
4. Is there significant correlation
between the performance of
Grade 6 students in Science and
Math?