# TIMSS Advanced 2015 Results

**scale creation**

The TIMSS Advanced international achievement scales were developed based on item response theory and population models using plausible values, with each student respondent being assigned five plausible values on each of the achievement scales.

Scale scores range from 0 to 1000.

Each international scale was established by TIMSS Advanced 1995 to have a midpoint of 500 located at the mean of the combined achievement distribution across all countries and to have 100 scale score points correspond to one standard deviation of the combined distribution.

In order to measure trends over time, the results of all subsequent TIMSS Advanced assessments (2008, 2015) were transformed onto this metric.

**OVERVIEW OF ACHIEVEMENT SCALES**

- Overall achievement (advanced mathematics and physics)
- Content domains
- Advanced mathematics: algebra, calculus, geometry
- Physics: mechanics and thermodynamics, electricity and magnetism, wave phenomena and atomic/nuclear physics

- Cognitive domains (advanced mathematics and physics)
- Knowing
- Applying
- Reasoning

Overall achievement results were reported in terms of the percentages of students reaching the following three benchmarks:

- Advanced International Benchmark (625)
- High International Benchmark (550)
- Intermediate International Benchmark (475)

The descriptions of the competencies of students reaching each of these benchmarks were determined by means of a scale-anchoring process.

**Scale creation**

For TIMSS Advanced 2015 a number of background questionnaire scales were created in order to report the context questionnaire data.

Scales were calculated using item response theory (IRT), specifically a Rasch partial credit model.

In addition, categorical variables were created using these scales by classifying respondents into one of three groups: High, Middle, and Low. Cut-off points for categorization were determined on a scale-by-scale basis.

**Questionnaire Scales**

- Home Environment and Future Plans (Advanced Mathematics and Physics)
- Home Educational Resources

- School Climate (Advanced Mathematics and Physics)
- School Supports Advanced Mathematics and Physics Education – Principal Version
- School Supports Advanced Mathematics and Physics Education – Teacher Version
- Teacher Job Satisfaction
- Students’ Sense of School Belonging

- School Safety (Advanced Mathematics and Physics)
- School Discipline Problems – Principals’ Reports
- Safe and Orderly School – Teachers’ Reports

- Student Engagement and Attitudes
- Students’ Views on Engaging Teaching in Advanced Mathematics Lessons (Advanced Mathematics)
- Students’ Views on Engaging Teaching in Physics Lessons (Physics)
- Students Like Learning Advanced Mathematics (Advanced Mathematics)
- Students Like Learning Physics (Physics)
- Students Value Advanced Mathematics (Advanced Mathematics)
- Students Value Physics (Physics)

**Advanced Mathematics**

- Countries:
- The 2% of Russian students in intensive study (6 hours-plus per week) and the 4% of Lebanese students in TIMSS Advanced had the highest achievement.
- The Russian Federation, with a total of 10% of its students in TIMSS Advanced, the United States with 11%, and Portugal with 29% (nearly three times that of Russia and the U.S.) had the next highest levels of achievement.

- Trend (1995–2015): Of the six countries with 20-year trend data, France, Italy, and Sweden had lower average achievement in 2015 than in 1995.
- The Russian Federation, Slovenia, and the United States showed no significant difference.
- Norway and Sweden had upturns between 2008 and 2015.

- More male students than female students were enrolled in advanced mathematics programs in six countries.

**Physics**

- Countries:
- Slovenia, with 8% of its students in TIMSS Advanced physics, had the highest average physics achievement.
- The Russian Federation, with 5% of its students in TIMSS Advanced, and Norway with 7% had the next highest achievement.
- Italy (18%) and France (22%) had the highest percentages of students in TIMSS Advanced physics, but the lowest average achievement.

- Trend (1995–2015): Of the six countries with 20-year trend data, France, Norway, the Russian Federation, and Sweden have experienced substantial decreases in average achievement since 1995, while Slovenia and the United States showed no significant change.
- No country improved over the 20-year period.

- More male students than female students were enrolled in physics programs in all countries.

**Context for Education**

- Schools
- In nearly all TIMSS Advanced countries, students attending schools with more affluent than disadvantaged students had on average higher levels of achievement.

- Teachers and teaching:
- Mathematics and physics teachers of TIMSS Advanced students reported high levels of education and considerable experience.

- Positive student attitudes toward the respective subjects were associated with higher achievement.