Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Supported by

Different Shapiro-Wilk test results in R, JASP and SPSS?

Hi everyone,
I know this isn't strictly speaking a Bayes question but it's a JASP question.

I've run the Shapiro-Wilk test on the same data in all three platforms and SPSS gives me W=.789, p=.027; R gives me W=.766, p=.008 and JASP gives me W=.804, p=.022.

What should I do here?

Is there any objective reason as to why this should be the case?


  • JASP uses an R package for this, must be the settings that make the difference. I'll ask Johnny to look into this.

  • Thank you. I was mildly confused by SPSS and R differing but I expected JASP to be the exact same as R because I knew it 'runs on R'.

    This is for my thesis. How do I know which one of them to report? I've got some cases where one of them shows S-W as significant and in others it doesn't..

  • We'll look into it. If you are really eager, you can inspect the JASP code on GitHub and see what arguments to the R function we call. I'm inclined to trust R over SPSS, but that's a general prior value judgement.

  • I was using R to begin with and my analyses currently are based on the R Shapiro-Wilk tests. Was using them to determine which inferential stats to use. So I'll report the R ones for now but please do let me know what happens with the difference between JASP and R.

  • Hi,
    I just looked into this, and JASP uses the shapiro.test() function in R. For the two-sample t-test, JASP does this separately for each group, so you get two Shapiro statistics and p-values. It might be the case that you calculated the aggregated Shapiro statistic across the two groups, leading to a different value. So for instance, for the kitchen rolls example dataset in JASP:

    shapiro.test(x = kitchenDat$mean_NEO) # to get the overall Shapiro statistic
    shapiro.test(x = kitchenDat$mean_NEO[kitchenDat$Rotation == "clock"]) # separate per condition
    shapiro.test(x = kitchenDat$mean_NEO[kitchenDat$Rotation == "counter"])

    If you repeat this with the one sample t-test in JASP, you get the first result, and if you run the Shapiro test with the two sample t-test in JASP, you get the latter two results. I do not have access to SPSS, so I'm not sure what they do with the test.
    In case this is not the reason for the differing results, could you please include a data example and R-code used to calculate the Shaprio statistics?
    Kind regards,

Sign In or Register to comment.

agen judi bola , sportbook, casino, togel, number game, singapore, tangkas, basket, slot, poker, dominoqq, agen bola. Semua permainan bisa dimainkan hanya dengan 1 ID. minimal deposit 50.000 ,- bonus cashback hingga 10% , diskon togel hingga 66% bisa bermain di android dan IOS kapanpun dan dimana pun. poker , bandarq , aduq, domino qq , dominobet. Semua permainan bisa dimainkan hanya dengan 1 ID. minimal deposit 10.000 ,- bonus turnover 0.5% dan bonus referral 20%. Bonus - bonus yang dihadirkan bisa terbilang cukup tinggi dan memuaskan, anda hanya perlu memasang pada situs yang memberikan bursa pasaran terbaik yaitu Bola168. Situs penyedia segala jenis permainan poker online kini semakin banyak ditemukan di Internet, salah satunya TahunQQ merupakan situs Agen Judi Domino66 Dan BandarQ Terpercaya yang mampu memberikan banyak provit bagi bettornya. Permainan Yang Di Sediakan Dewi365 Juga sangat banyak Dan menarik dan Peluang untuk memenangkan Taruhan Judi online ini juga sangat mudah . Mainkan Segera Taruhan Sportbook anda bersama Agen Judi Bola Bersama Dewi365 Kemenangan Anda Berapa pun akan Terbayarkan. Tersedia 9 macam permainan seru yang bisa kamu mainkan hanya di dalam 1 ID saja. Permainan seru yang tersedia seperti Poker, Domino QQ Dan juga BandarQ Online. Semuanya tersedia lengkap hanya di ABGQQ. Situs ABGQQ sangat mudah dimenangkan, kamu juga akan mendapatkan mega bonus dan setiap pemain berhak mendapatkan cashback mingguan. ABGQQ juga telah diakui sebagai Bandar Domino Online yang menjamin sistem FAIR PLAY disetiap permainan yang bisa dimainkan dengan deposit minimal hanya Rp.25.000. DEWI365 adalah Bandar Judi Bola Terpercaya & resmi dan terpercaya di indonesia. Situs judi bola ini menyediakan fasilitas bagi anda untuk dapat bermain memainkan permainan judi bola. Didalam situs ini memiliki berbagai permainan taruhan bola terlengkap seperti Sbobet, yang membuat DEWI365 menjadi situs judi bola terbaik dan terpercaya di Indonesia. Tentunya sebagai situs yang bertugas sebagai Bandar Poker Online pastinya akan berusaha untuk menjaga semua informasi dan keamanan yang terdapat di POKERQQ13. Kotakqq adalah situs Judi Poker Online Terpercayayang menyediakan 9 jenis permainan sakong online, dominoqq, domino99, bandarq, bandar ceme, aduq, poker online, bandar poker, balak66, perang baccarat, dan capsa susun. Dengan minimal deposit withdraw 15.000 Anda sudah bisa memainkan semua permaina pkv games di situs kami. Jackpot besar,Win rate tinggi, Fair play, PKV Games