在实施autoform的测试代码时收到以下错误。克隆运行正常。我已经安装了包：aldeed。错误在哪里？
Error: Invalid definition for firstName field.
W20150407-15:40:16.988(5.5)? (STDERR) at packages/aldeed:simple-schema/simple-schema.js:62:1
W20150407-15:40:16.988(5.5)? (STDERR) at Function._.each._.forEach (packages/underscore/underscore.js:113:1)
W20150407-15:40:16.988(5.5)? (STDERR) at [object Object].SimpleSchema (packages/aldeed:simple-schema/simple-schema.js:59:1)
W20150407-15:40:16.988(5.5)? (STDERR) at app/common/1_schemas.js:5:18
W20150407-15:40:16.988(5.5)? (STDERR) at app/common/1_schemas.js:123:3
W20150407-15:40:16.988(5.5)? (STDERR) at /home/garima.wadhera/autoform/.meteor/local/build/programs/server/boot.js:222:10
W20150407-15:40:16.989(5.5)? (STDERR) at Array.forEach (native)
W20150407-15:40:16.989(5.5)? (STDERR) at Function._.each._.forEach (/root/.meteor/packages/meteor-tool/.1.1.2.2ai5r5++os.linux.x86_64+web.browser+web.cordova/mt-os.linux.x86_64/dev_bundle/server-lib/node_modules/underscore/underscore.js:79:11)
W20150407-15:40:16.989(5.5)? (STDERR) at /home/garima.wadhera/autoform/.meteor/local/build/programs/server/boot.js:117:5