Experimental Design and Power

Glass Delta Effect Size Calculator

Calculates Glass’s delta using the control-group standard deviation. The form displays (mean1−mean2)/control SD beside glass delta effect size, using a worked condition that can be recalculated with the labeled inputs.

Design and power inputs

Set the labeled inputs

units
units
units
Calculated result

Glass Delta Effect Size

Result
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(mean1−mean2)/control SD

    Interpreting the requested glass delta effect size

    The glass delta effect size page calculates Glass’s delta using the control-group standard deviation.

    Glass Delta Effect Size is limited to the statistical quantity named by the result panel. The glass delta effect size calculation does not silently add a population, time horizon, causal direction, or decision threshold that is absent from the fields.

    Inputs that define glass delta effect size

    • Treatment mean: For glass delta effect size, the worked value for treatment mean is 82 units. Treat the treatment mean entry (82 units) explicitly as a count, proportion, rate, estimate, or model parameter before comparing glass delta effect size conditions.
    • Control mean: For glass delta effect size, the worked value for control mean is 75 units. Treat the control mean entry (75 units) explicitly as a count, proportion, rate, estimate, or model parameter before comparing glass delta effect size conditions.
    • Control SD: For glass delta effect size, the worked value for control sd is 8 units. Treat the control sd entry (8 units) explicitly as a count, proportion, rate, estimate, or model parameter before comparing glass delta effect size conditions. The form enforces minimum 1e-06.

    The entries used for glass delta effect size must refer to one coherent analysis condition. Combining incompatible populations, periods, or measurement definitions can produce valid glass delta effect size arithmetic for a nonexistent study.

    From inputs to glass delta effect size

    (mean1−mean2)/control SD

    For glass delta effect size, match every symbol in the relationship to a labeled field before substituting numbers. Glass Delta Effect Size is reported in the scale implied by the inputs and formula.

    While checking glass delta effect size, inspect every denominator in (mean1−mean2)/control SD. For glass delta effect size, a zero or near-zero denominator can make glass delta effect size undefined or unstable.

    Verifying the default glass delta effect size result

    The default glass delta effect size condition is Treatment mean = 82 units, Control mean = 75 units, Control SD = 8 units.

    Means 82 and 75 with control SD 8 produce delta = 0.875.

    The live calculator reports Glass delta 0.875. Repeating one intermediate step from (mean1−mean2)/control SD provides a fixed glass delta effect size reference check for later code changes.

    Limits on interpreting glass delta effect size

    Using the control spread is useful when treatment variability may differ, but that choice should be explicit.

    For glass delta effect size, power and design calculations are prospective scenarios, not guarantees. For glass delta effect size, their answer changes when the planned effect, variance, allocation, alpha, or attrition assumption changes.

    Reading glass delta effect size in context

    When interpreting glass delta effect size, report the design inputs as assumptions and compare at least one plausible alternative before committing resources to the plan.

    As a second check for glass delta effect size, reversing the numerator and denominator answers a different question, so retain the direction printed in (mean1−mean2)/control SD.

    Testing how stable glass delta effect size is

    Change treatment mean while holding the remaining entries fixed, then state why the direction and size of the glass delta effect size change are plausible from (mean1−mean2)/control SD.

    Repeat the glass delta effect size exercise with control sd. If a modest defensible change materially alters the interpretation, report both conditions rather than presenting that glass delta effect size scenario as exact.

    What to record with glass delta effect size

    Report glass delta effect size using (mean1−mean2)/control SD, followed by the entered values, units, exclusions, and analysis date. Name the glass delta effect size population or dataset boundary instead of leaving it implicit.

    Keep the full calculator output with the record, including Glass delta 0.875. A later glass delta effect size review can then distinguish a changed input from a different convention or software implementation.

    Questions about glass delta effect size

    What should be saved with glass delta effect size?

    Save the entered values and units for treatment mean, control mean, control sd, along with the analysis date, exclusions, software or formula version, and the relationship (mean1−mean2)/control SD. That record is sufficient to rebuild this specific glass delta effect size calculation.

    Does glass delta effect size establish a causal or population conclusion?

    No. The displayed glass delta effect size value is conditional on the entered data and named method. The glass delta effect size design, measurement process, and assumptions determine what can be concluded beyond those values.

    How should glass delta effect size be rounded?

    Keep the unrounded glass delta effect size for subsequent arithmetic, then report only the precision supported by the source measurements and the decision context. Extra digits in glass delta effect size do not correct sampling or model error.

    Which input deserves the closest boundary check?

    For glass delta effect size, start with control sd and then treatment mean. Confirm the glass delta effect size units and allowed domain because a valid-looking entry can still describe the wrong statistical setup.

    Why could another program report a different glass delta effect size?

    A different convention for rounding, tails, ties, interpolation, parameterization, or missing values can change glass delta effect size. Compare the printed glass delta effect size formula and its input definitions before treating either output as wrong.

    What does glass delta effect size represent on this page?

    It is the quantity produced by (mean1−mean2)/control SD from the displayed treatment mean, control mean, control sd. This page calculates Glass’s delta using the control-group standard deviation.