APA 7 Numerical Values

 

APA 7 Numerical Values

• Decimal values: APA 7 requires a leading zero before the decimal for values less than one when the statistic can be greater than one (e.g., p = 0.01), and omits the leading zero when it cannot exceed one (e.g., r = .45). You’ve mostly followed this, but there are a few small inconsistencies (e.g.,
• in p-values, “p < .01” is correct,
• reliability coefficients you should keep the leading zero: α = 0.87).
• Ensure spaces are placed before and after equals signs in statistical reporting (e.g., PNI_modified = 0.53).
• Percentages are correctly expressed with the % sign and a numeral (APA 7 allows this).

in APA Style (7th edition), fit indices such as RMR, RMSEA, CFI, TLI, SRMR, and similar goodness-of-fit statistics are not italicized.

Here’s the general APA convention:

• Symbols for test statistics (e.g., t, F, p, r, d, M, SD) → italicized because they are statistical symbols.
• Named indices or acronyms (e.g., RMSEA, CFI, GFI, AIC) → written in regular font, capitalized, no italics.
• Greek letters (e.g., χ²) → italicized because they are mathematical/statistical symbols, not acronyms.

So, in your excerpt:

• χ² → italicized because it’s a statistical symbol.
• RMSEA and CFI → regular (non-italic) font.

χ²(46) = 32.19, p = .94, RMSEA = 0.00, CFI = 1.00

(APA prefers p-values in the form p = .94 rather than p = 0.94.)

 in APA Style, table headings are not italicized.

Here’s how it breaks down for your example:

• Column and row headers (e.g., Groups, Factors/Variables, Position, Total, Teachers, Supervisors) → regular font, no italics, but APA recommends sentence case (only the first word and proper nouns capitalized).
• Statistical symbols inside the table (e.g., β, t, R²) → italicized because they are symbols.
• Factor names (e.g., Solutions (SOL): Ability to solve problems) → regular font, unless you’re referencing a scale title, in which case APA says to italicize scale titles (not the variables themselves).

So your table headings would look like this in APA style:

Groups	Factors/variables	Position	Total
	Teachers
	β t R²
	Supervisors
	β t R²

It sounds like you’re asking about the coefficient of determination, R2R^2R2, and whether it can be zero — possibly in the context where R2≥0.75R^2 \geq 0.75R2≥0.75 is also mentioned.

Here’s the breakdown:

• What R2R^2R2 is:
  R2R^2R2 measures how well a model explains the variance in the dependent variable.
• R2=1R^2 = 1R2=1 → perfect fit.
• R2=0R^2 = 0R2=0 → model explains none of the variance (predictions are no better than simply using the mean).
• R2<0R^2 < 0R2<0 can occur if the model fits worse than a horizontal line at the mean.
• Can R2R^2R2 be zero?
  Yes — R2=0R^2 = 0R2=0 is possible. It means the model’s predictions are completely uncorrelated with the observed data.
  But if you state R2≥0.75 R^2 \geq 0.75R2≥0.75, then you are imposing a constraint: in that case, R2R^2R2 cannot be zero because 0 is less than 0.75.

So:

• Without constraint: Yes, R2R^2R2 can be zero.
• With R2≥0.75 R^2 \geq 0.75R2≥0.75 requirement: No, zero is excluded by definition.

ChatGPT said:

In APA 7th edition, the correct way to report R2R^2R2 (and similar statistics) depends on the context, but there are some consistent rules.

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1. Basic format for reporting R2R^2R2

• Use italic for the symbol: R2R^2R2
• Include two decimal places (unless your field requires more)
• If reporting adjusted R2R^2R2, write it as adjusted R2R^2R2.

Example:

The model explained a significant proportion of variance in scores, R2=.76,F(3,96)=12.45,p<.001R^2 = .76, F(3, 96) = 12.45, p < .001R2=.76,F(3,96)=12.45,p<.001.

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2. When R2R^2R2 is a main result

• State clearly what the variance represents (what is predicted).
• Include the FFF-test and degrees of freedom if from regression.
• Mention adjusted R2R^2R2 if used.

Example:

A linear regression was conducted to predict exam scores from study time, motivation, and sleep hours. The model was significant, F(3,96)=12.45,p<.001F(3, 96) = 12.45, p < .001F(3,96)=12.45,p<.001, and explained 76% of the variance in exam scores, R2=.76R^2 = .76R2=.76.

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3. APA 7 notes for style

• Leading zero: Omit before the decimal for values < 1 (write .76, not 0.76).
• p-values: Write as p=.032p = .032p=.032 or p<.001p < .001p<.001.
• Rounding: Usually 2 decimal places, but keep more if rounding would change the interpretation (e.g., .004 vs .00).

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4. Example with adjusted R2R^2R2

The model accounted for a significant proportion of the variance in anxiety scores, R2=.32R^2 = .32R2=.32, adjusted R2=.29,F(5,114)=10.42,p<.001R^2 = .29, F(5, 114) = 10.42, p < .001R2=.29,F(5,114)=10.42,p<.001.

In APA 7th edition, you’d write the standard deviation like this:

• Symbol in italics: SD
• Numerical value rounded appropriately (usually two decimal places)
• Leading zero included before the decimal for values < 1

Example:

SD = 0.57

In-text example:

The participants’ mean anxiety score was 4.21 (SD = 0.57).

If you like, I can also show you the APA 7 full sentence format for reporting M and SD together.