### Abstract

This article describes a program, PRODCLIN (distribution of the PRODuct Confidence Limits for INdirect effects), written for SAS, SPSS, and R, that computes confidence limits for the product of two normal random variables. The program is important because it can be used to obtain more accurate confidence limits for the indirect effect, as demonstrated in several recent articles (MacKinnon, Lockwood, & Williams, 2004; Pituch, Whittaker, & Stapleton, 2005). Tests of the significance of and confidence limits for indirect effects based on the distribution of the product method have more accurate Type I error rates and more power than other, more commonly used tests. Values for the two paths involved in the indirect effect and their standard errors are entered in the PRODCLIN program, and distribution of the product confidence limits are computed. Several examples are used to illustrate the PRODCLIN program. The PRODCLIN programs in rich text format may be downloaded from www.psychonomic.org/archive.

Original language | English (US) |
---|---|

Pages (from-to) | 384-389 |

Number of pages | 6 |

Journal | Behavior Research Methods |

Volume | 39 |

Issue number | 3 |

State | Published - Aug 2007 |

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### ASJC Scopus subject areas

- Psychology(all)
- Psychology (miscellaneous)
- Experimental and Cognitive Psychology

### Cite this

*Behavior Research Methods*,

*39*(3), 384-389.

**Distribution of the product confidence limits for the indirect effect : Program PRODCLIN.** / Mackinnon, David; Fritz, Matthew S.; Williams, Jason; Lockwood, Chondra M.

Research output: Contribution to journal › Article

*Behavior Research Methods*, vol. 39, no. 3, pp. 384-389.

}

TY - JOUR

T1 - Distribution of the product confidence limits for the indirect effect

T2 - Program PRODCLIN

AU - Mackinnon, David

AU - Fritz, Matthew S.

AU - Williams, Jason

AU - Lockwood, Chondra M.

PY - 2007/8

Y1 - 2007/8

N2 - This article describes a program, PRODCLIN (distribution of the PRODuct Confidence Limits for INdirect effects), written for SAS, SPSS, and R, that computes confidence limits for the product of two normal random variables. The program is important because it can be used to obtain more accurate confidence limits for the indirect effect, as demonstrated in several recent articles (MacKinnon, Lockwood, & Williams, 2004; Pituch, Whittaker, & Stapleton, 2005). Tests of the significance of and confidence limits for indirect effects based on the distribution of the product method have more accurate Type I error rates and more power than other, more commonly used tests. Values for the two paths involved in the indirect effect and their standard errors are entered in the PRODCLIN program, and distribution of the product confidence limits are computed. Several examples are used to illustrate the PRODCLIN program. The PRODCLIN programs in rich text format may be downloaded from www.psychonomic.org/archive.

AB - This article describes a program, PRODCLIN (distribution of the PRODuct Confidence Limits for INdirect effects), written for SAS, SPSS, and R, that computes confidence limits for the product of two normal random variables. The program is important because it can be used to obtain more accurate confidence limits for the indirect effect, as demonstrated in several recent articles (MacKinnon, Lockwood, & Williams, 2004; Pituch, Whittaker, & Stapleton, 2005). Tests of the significance of and confidence limits for indirect effects based on the distribution of the product method have more accurate Type I error rates and more power than other, more commonly used tests. Values for the two paths involved in the indirect effect and their standard errors are entered in the PRODCLIN program, and distribution of the product confidence limits are computed. Several examples are used to illustrate the PRODCLIN program. The PRODCLIN programs in rich text format may be downloaded from www.psychonomic.org/archive.

UR - http://www.scopus.com/inward/record.url?scp=34548453393&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34548453393&partnerID=8YFLogxK

M3 - Article

C2 - 17958149

AN - SCOPUS:34548453393

VL - 39

SP - 384

EP - 389

JO - Behavior Research Methods, Instruments, and Computers

JF - Behavior Research Methods, Instruments, and Computers

SN - 1554-351X

IS - 3

ER -