psppire: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/psppire - from package: pspp

You may install the required package with command apt-get install {package}
Error in other languages:
psppire: bevel nie gevind nie
psppire: comandă negăsită
psppire: comando não encontrado
psppire: commande introuvable
psppire: command not found
psppire: käsku ei ole
psppire: không tìm thấy lệnh
psppire: komanda nerasta
psppire: Kommando nicht gefunden.
psppire: kommandot finns inte
psppire: komut yok
psppire: nie znaleziono polecenia
psppire: níor aimsíodh an t-ordú
psppire: no se encontró la orden
psppire: no s'ha trobat l'ordre
psppire: opdracht niet gevonden
psppire: parancs nem található
psppire: perintah tidak ditemukan
psppire: príkaz nenájdený
psppire: příkaz nenalezen
psppire: команда не найдена
psppire: командата не е открита
psppire: 命令找不到
psppire: コマンドが見つかりません