vare: Sampling Error Variance

In psychometric: Applied Psychometric Theory

Sampling Error Variance

Description

Computes sampling error variance in correlations from a data object of the general format found in EnterMeta

Usage

vare(x)
aprox.vare(x)
vare36(x)

Arguments

x	A matrix or data.frame with columns Rxy and n: see EnterMeta

Details

vare is the 'core' equation for estimating the sampling error variance. Presumably because of the history of meta-analysis and lack of desktop computing power, hand-calculatons were needed. Thus, two additional equations were developed. The aprox.vare appears in many textbooks and is used often (Arthur et al.). Another variation is presented by Hunter & Schmidt (2004) as their equation 3.6 vare36.

Value

Sampling error variance (exact, approximate, or alternate aproximate)

Note

The equations for each function are:
vare <- sum(n*(1-rb^2)^2/(n-1),na.rm=TRUE)/sum(n,na.rm=TRUE)
aprox.vare <- (1-rb^2)^2/(mean(n, na.rm=TRUE)-1)
vare36 <- ((1-rb^2)^2*k)/T where k is number of studies and T is total sample size

These are only presented here for completeness. The recommended equation is vare.

Author(s)

Thomas D. Fletcher [e-mail]

References

Arthur, Jr., W., Bennett, Jr., W., and Huffcutt, A. I. (2001) Conducting Meta-analysis using SAS. Mahwah, NJ: Erlbaum.

Hunter, J.E. and Schmidt, F.L. (2004). Methods of meta-analysis: Correcting error and bias in research findings (2nd ed.). Thousand Oaks: Sage Publications.

Hunter, J.E., Schmidt, F.L., and Jackson, G.B. (1982). Meta-analysis: Cumulating research findings across studies. Beverly Hills: Sage Publications.

See Also

varr, rbar

Examples

# From Arthur et al
data(ABHt32)
vare(ABHt32)
aprox.vare(ABHt32)
vare36(ABHt32)
# From Hunter et al
data(HSJt35)
vare(HSJt35)
aprox.vare(HSJt35)
vare36(HSJt35)

psychometric documentation built on Nov. 6, 2023, 1:06 a.m.