Myers Blended Sex Ratio Index Calculator
Compute Myers' blended index of sex ratios, the sum over terminal digits 0-9 of absolute deviations of blended sex ratios from 100, using overlapping age windows to remove digit-weighting bias.
Description
Compute Myers' blended index of sex ratios, the sum over terminal digits 0-9 of absolute deviations of blended sex ratios from 100, using overlapping age windows to remove digit-weighting bias.
Compute Myers' blended index of sex ratios, the sum over terminal digits 0-9 of absolute deviations of blended sex ratios from 100, using overlapping age windows to remove digit-weighting bias.1
When to use Myers Blended Sex Ratio Index Calculator
Use this diagnostic to identify suspicious digit preference or age-sex patterns before fitting rates, life tables, or population projections.
- Males
- Males at each single year of age starting with the minimum age.
- Females
- Females at each single year of age, aligned with the males.
- Start age
- Age of the first entry in both lists.
How the method works
- Myers index
- Sum of |blended sex ratio - 100| across terminal digits; zero is ideal.
- Blended SR
- Blended sex ratio for each terminal digit 0 through 9.
Limitations and assumptions
These indices are screening diagnostics, not corrections. Their thresholds depend on the stated age window and can also respond to real cohort variation, migration, conflict, or selective undercoverage.
Alternative or Complementary measures
Inspect the underlying age distribution and compare more than one diagnostic, such as Whipple, Myers, or the UN joint score. A graphical population pyramid can reveal cohort patterns that a single index compresses.
References
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Age heaping — Wikipedia contributors
Similar or alternative tools
- Bachi Age-Sex Accuracy Index Calculator
Compute Bachi's age-sex accuracy index, the sum over both sexes of half the total absolute deviation of terminal-digit shares from ten percent across complete decades of single ages.
- UN Joint Age Sex Score
Compute the UN Manual IV joint score for age-sex data quality: three times the sum of absolute successive sex-ratio deviations plus the summed male and female age-ratio deviations, classifying below 20 as accurate, 20 to 40 as inaccurate and above 40 as highly inaccurate.
- Whipple Age Heaping Index Calculator
Compute the classic Whipple index of age heaping over ages 23-62, reporting both the five-fold-scaled index and the raw share of reported ages ending in 0 or 5, with UN quality bands. A custom inclusive evaluation window may also be supplied.