Errata - Correction Notice

There were several errors in Table 1 of the paper by Bem, Palmer, and Broughton entided "Updating the ganzfeld database: A victim of its own success?" that appeared in our September 2001 issue (JP, 65, 210-211). A corrected table appears below. The errors involved: "Trials" for "Dalton (1997)" and "Willin (1996a)"; "Hit rate %" for "Broughton & Alexander (1997) - First Timer's Series 2"; "Standardness" for "Kanthamani & Khilji (1990) - Series 6b"; "z score" and "ES' for "McDonough et al. (1994)". The errors regarding McDonough et al. were discovered by Palmer following publication of Bem et al. They originated in the earlier ganzfeld meta-analysis paper by Milton and Wiseman (Psychological Bulletin, 125, 387-391). Taking them into account has only a minor effect on the statistics in Bem et al. and does not alter any of their conclusions. The other errors were typesetting mistakes and did not figure into the computation of the statistics.

TABLE 1

NUMBER OF TRIALS, z SCORE, EFFECT SIZE (ES), HIT RATE, AND STANDARDNESS
RATING FOR EACH STUDY IN THE UPDATED GANZFELD DATABASE (ARRANGED IN
ORDER OF DECREASING STANDARDNESS)

    Study                               Trials      z     ES  Hit
                                                score         rate
                                                               %

    Bierman et al. (1993) - Series I      50     0.03   0.00  26.0
    Bierman et al. (1993) - Series II     50    -0.30  -0.04  24.0
    Broughton & Alexander (1997) -        50    -0.30  -0.04  24.0
     First Timers Series l (a)
    Broughton & Alexander (1997) -        50    -1.33  -0.19  18.0
     First Timers Series 2 (a)
    Broughton & Alexander (1997) -        51     1.81   0.25  37.3
     Emotionally Close Series (a)
    Dalton (1994)                         29     1.76   0.33  41.4
(*) Dalton (1997)                        128     5.20   0.46  46.9
    Morris et al. (1993)-                 32     1.78   0.31  40.6
     Cunningham Study
(*) Alexander & Broughton (1999)          50     1.60   0.23  36.0
    Broughton & Alexander (1997) (a) -    50    -0.64  -0.09  22.0
     Clairvoyance Series
    Broughton & Alexander (1997) (a) -     8     0.46   0.16  37.5
     General Series
    Kanthamani & Broughton (1994)         40    -0.91  -0.14  20.0
     Series 3
    Kanthamani & Broughton (1994) -       65     2.01   0.25  36.9
     Series 4
    Parker et al. (1997) -                30     1.25   0.23  36.7
     Study 2 (b)
    Parker et al. (1997) -                30     1.25   0.23  36.7
     Study 3 (b)
(*) Parker & Westerlund (1998) -          30     2.40   0.44  46.7
     Study 4
(*) Parker & Westerlund (1998) -          30     1.25   0.23  36.7
     Study 5
    Kanthamani & Palmer (1993)            22    -2.17  -0.46   9.1
    Morris et al. (1995)                  97     1.67   0.17  33.0
    Kanthamani & Broughton (1994) -       50     0.03   0.00  26.0
     Series 8
    Morris et al. (1993) -                32    -0.17  -0.03  25.0
     McAlpine Study
    Stanford & Frank (1991)               58    -1.24  -0.16  19.0 (d)
    Kanthamani & Broughton (1994) -       46     0.03   0.00  26.1
     Series 7
    McDonough et al. (1994)               20     0.30   0.07  30.0
    Parker et al. (1997) -                30    -0.83  -0.15  20.0
     Study l (b)
    Williams et al. (1994)                42    -2.30  -0.35  11.9
(*) Wezelman et al. (1997)                32     2.15   0.38  43.8
    Bierman (1995) - Series III           40     1.94   0.31  40.0
    Bierman (1995) - Series IV            36     1.33   0.22  36.1
(*) Symmons & Morris (1997)               51     2.97   0.42  45.1
(*) Wezelman & Bierman (1997) -           32    -1.45  -0.26  15.6
     Series IV
    Kanthamani & Khilji (1990) -          40     0.52   0.08  30.0 (d)
     Series 6b (c)
    Kanthamani & Broughton (1992) -       20    -0.46  -0.10  25.0 (d)
     Series 6a (c)
(*) Parker & Westerlund (1998) -          30    -0.49  -0.09  23.0 (d)
     Serial Study
(*) Wezelman & Bierman (1997) -           40    -0.91  -0.14  20.0
     Series V
(*) Wezelman & Bierman (1997) -           40    -0.15  -0.02  25.0
     Series VI
    Kanthamani et al. (1988) -             4     0.22   0.11  50.0 (d)
     Series 5a (c)
    Kanthamani et al. (1988) -            10    -2.06  -0.65  10.0 (d)
     Series 5b (c)
    Willin (1996a)                       100    -0.33  -0.03  24.0
    Willin (1996b)                        16    -0.24  -0.06  25.0

    Study                               Stan-
                                        dard-
                                         ness

    Bierman et al. (1993) - Series I     7.00
    Bierman et al. (1993) - Series II    7.00
    Broughton & Alexander (1997) -       7.00
     First Timers Series l (a)
    Broughton & Alexander (1997) -       7.00
     First Timers Series 2 (a)
    Broughton & Alexander (1997) -       7.00
     Emotionally Close Series (a)
    Dalton (1994)                        7.00
(*) Dalton (1997)                        7.00
    Morris et al. (1993)-                7.00
     Cunningham Study
(*) Alexander & Broughton (1999)         6.67
    Broughton & Alexander (1997) (a) -   6.67
     Clairvoyance Series
    Broughton & Alexander (1997) (a) -   6.67
     General Series
    Kanthamani & Broughton (1994)        6.67
     Series 3
    Kanthamani & Broughton (1994) -      6.67
     Series 4
    Parker et al. (1997) -               6.67
     Study 2 (b)
    Parker et al. (1997) -               6.67
     Study 3 (b)
(*) Parker & Westerlund (1998) -         6.67
     Study 4
(*) Parker & Westerlund (1998) -         6.67
     Study 5
    Kanthamani & Palmer (1993)           6.33
    Morris et al. (1995)                 6.33
    Kanthamani & Broughton (1994) -      6.00
     Series 8
    Morris et al. (1993) -               6.00
     McAlpine Study
    Stanford & Frank (1991)              5.67
    Kanthamani & Broughton (1994) -      5.33
     Series 7
    McDonough et al. (1994)              5.33
    Parker et al. (1997) -               5.33
     Study l (b)
    Williams et al. (1994)               5.33
(*) Wezelman et al. (1997)               4.67
    Bierman (1995) - Series III          4.33
    Bierman (1995) - Series IV           4.33
(*) Symmons & Morris (1997)              4.00
(*) Wezelman & Bierman (1997) -          4.00
     Series IV
    Kanthamani & Khilji (1990) -         3.67
     Series 6b (c)
    Kanthamani & Broughton (1992) -      3.33
     Series 6a (c)
(*) Parker & Westerlund (1998) -         3.33
     Serial Study
(*) Wezelman & Bierman (1997) -          3.00
     Series V
(*) Wezelman & Bierman (1997) -          3.00
     Series VI
    Kanthamani et al. (1988) -           2.67
     Series 5a (c)
    Kanthamani et al. (1988) -           2.67
     Series 5b (c)
    Willin (1996a)                       1.33
    Willin (1996b)                       1.33

Note: Asterisks denote studies added to Milton and Wiseman (1999).

(a)Cited as Broughton and Alexander (1996) in Milton and Wiseman (1999).

(b)Cited as Johansson and Parker (1995) in Milton and Wiseman (1999).

(c)Series summarized and numbered in Kanthamani and Broughton (1994).

(d)Hit rate not reported. Estimated from z score.

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