Atividade - Probabilidade Normal

Introdução

Este trabalho fará os cálculos das probabilidades apresentadas abaixo de uma distribuição normal.

Carregando os pacotes

library(RcmdrMisc)
library(dplyr)

Fatores

x = seq(-3.291, 3.291, length.out=1000)    
x
##    [1] -3.291000000 -3.284411411 -3.277822823 -3.271234234 -3.264645646
##    [6] -3.258057057 -3.251468468 -3.244879880 -3.238291291 -3.231702703
##   [11] -3.225114114 -3.218525526 -3.211936937 -3.205348348 -3.198759760
##   [16] -3.192171171 -3.185582583 -3.178993994 -3.172405405 -3.165816817
##   [21] -3.159228228 -3.152639640 -3.146051051 -3.139462462 -3.132873874
##   [26] -3.126285285 -3.119696697 -3.113108108 -3.106519520 -3.099930931
##   [31] -3.093342342 -3.086753754 -3.080165165 -3.073576577 -3.066987988
##   [36] -3.060399399 -3.053810811 -3.047222222 -3.040633634 -3.034045045
##   [41] -3.027456456 -3.020867868 -3.014279279 -3.007690691 -3.001102102
##   [46] -2.994513514 -2.987924925 -2.981336336 -2.974747748 -2.968159159
##   [51] -2.961570571 -2.954981982 -2.948393393 -2.941804805 -2.935216216
##   [56] -2.928627628 -2.922039039 -2.915450450 -2.908861862 -2.902273273
##   [61] -2.895684685 -2.889096096 -2.882507508 -2.875918919 -2.869330330
##   [66] -2.862741742 -2.856153153 -2.849564565 -2.842975976 -2.836387387
##   [71] -2.829798799 -2.823210210 -2.816621622 -2.810033033 -2.803444444
##   [76] -2.796855856 -2.790267267 -2.783678679 -2.777090090 -2.770501502
##   [81] -2.763912913 -2.757324324 -2.750735736 -2.744147147 -2.737558559
##   [86] -2.730969970 -2.724381381 -2.717792793 -2.711204204 -2.704615616
##   [91] -2.698027027 -2.691438438 -2.684849850 -2.678261261 -2.671672673
##   [96] -2.665084084 -2.658495495 -2.651906907 -2.645318318 -2.638729730
##  [101] -2.632141141 -2.625552553 -2.618963964 -2.612375375 -2.605786787
##  [106] -2.599198198 -2.592609610 -2.586021021 -2.579432432 -2.572843844
##  [111] -2.566255255 -2.559666667 -2.553078078 -2.546489489 -2.539900901
##  [116] -2.533312312 -2.526723724 -2.520135135 -2.513546547 -2.506957958
##  [121] -2.500369369 -2.493780781 -2.487192192 -2.480603604 -2.474015015
##  [126] -2.467426426 -2.460837838 -2.454249249 -2.447660661 -2.441072072
##  [131] -2.434483483 -2.427894895 -2.421306306 -2.414717718 -2.408129129
##  [136] -2.401540541 -2.394951952 -2.388363363 -2.381774775 -2.375186186
##  [141] -2.368597598 -2.362009009 -2.355420420 -2.348831832 -2.342243243
##  [146] -2.335654655 -2.329066066 -2.322477477 -2.315888889 -2.309300300
##  [151] -2.302711712 -2.296123123 -2.289534535 -2.282945946 -2.276357357
##  [156] -2.269768769 -2.263180180 -2.256591592 -2.250003003 -2.243414414
##  [161] -2.236825826 -2.230237237 -2.223648649 -2.217060060 -2.210471471
##  [166] -2.203882883 -2.197294294 -2.190705706 -2.184117117 -2.177528529
##  [171] -2.170939940 -2.164351351 -2.157762763 -2.151174174 -2.144585586
##  [176] -2.137996997 -2.131408408 -2.124819820 -2.118231231 -2.111642643
##  [181] -2.105054054 -2.098465465 -2.091876877 -2.085288288 -2.078699700
##  [186] -2.072111111 -2.065522523 -2.058933934 -2.052345345 -2.045756757
##  [191] -2.039168168 -2.032579580 -2.025990991 -2.019402402 -2.012813814
##  [196] -2.006225225 -1.999636637 -1.993048048 -1.986459459 -1.979870871
##  [201] -1.973282282 -1.966693694 -1.960105105 -1.953516517 -1.946927928
##  [206] -1.940339339 -1.933750751 -1.927162162 -1.920573574 -1.913984985
##  [211] -1.907396396 -1.900807808 -1.894219219 -1.887630631 -1.881042042
##  [216] -1.874453453 -1.867864865 -1.861276276 -1.854687688 -1.848099099
##  [221] -1.841510511 -1.834921922 -1.828333333 -1.821744745 -1.815156156
##  [226] -1.808567568 -1.801978979 -1.795390390 -1.788801802 -1.782213213
##  [231] -1.775624625 -1.769036036 -1.762447447 -1.755858859 -1.749270270
##  [236] -1.742681682 -1.736093093 -1.729504505 -1.722915916 -1.716327327
##  [241] -1.709738739 -1.703150150 -1.696561562 -1.689972973 -1.683384384
##  [246] -1.676795796 -1.670207207 -1.663618619 -1.657030030 -1.650441441
##  [251] -1.643852853 -1.637264264 -1.630675676 -1.624087087 -1.617498498
##  [256] -1.610909910 -1.604321321 -1.597732733 -1.591144144 -1.584555556
##  [261] -1.577966967 -1.571378378 -1.564789790 -1.558201201 -1.551612613
##  [266] -1.545024024 -1.538435435 -1.531846847 -1.525258258 -1.518669670
##  [271] -1.512081081 -1.505492492 -1.498903904 -1.492315315 -1.485726727
##  [276] -1.479138138 -1.472549550 -1.465960961 -1.459372372 -1.452783784
##  [281] -1.446195195 -1.439606607 -1.433018018 -1.426429429 -1.419840841
##  [286] -1.413252252 -1.406663664 -1.400075075 -1.393486486 -1.386897898
##  [291] -1.380309309 -1.373720721 -1.367132132 -1.360543544 -1.353954955
##  [296] -1.347366366 -1.340777778 -1.334189189 -1.327600601 -1.321012012
##  [301] -1.314423423 -1.307834835 -1.301246246 -1.294657658 -1.288069069
##  [306] -1.281480480 -1.274891892 -1.268303303 -1.261714715 -1.255126126
##  [311] -1.248537538 -1.241948949 -1.235360360 -1.228771772 -1.222183183
##  [316] -1.215594595 -1.209006006 -1.202417417 -1.195828829 -1.189240240
##  [321] -1.182651652 -1.176063063 -1.169474474 -1.162885886 -1.156297297
##  [326] -1.149708709 -1.143120120 -1.136531532 -1.129942943 -1.123354354
##  [331] -1.116765766 -1.110177177 -1.103588589 -1.097000000 -1.090411411
##  [336] -1.083822823 -1.077234234 -1.070645646 -1.064057057 -1.057468468
##  [341] -1.050879880 -1.044291291 -1.037702703 -1.031114114 -1.024525526
##  [346] -1.017936937 -1.011348348 -1.004759760 -0.998171171 -0.991582583
##  [351] -0.984993994 -0.978405405 -0.971816817 -0.965228228 -0.958639640
##  [356] -0.952051051 -0.945462462 -0.938873874 -0.932285285 -0.925696697
##  [361] -0.919108108 -0.912519520 -0.905930931 -0.899342342 -0.892753754
##  [366] -0.886165165 -0.879576577 -0.872987988 -0.866399399 -0.859810811
##  [371] -0.853222222 -0.846633634 -0.840045045 -0.833456456 -0.826867868
##  [376] -0.820279279 -0.813690691 -0.807102102 -0.800513514 -0.793924925
##  [381] -0.787336336 -0.780747748 -0.774159159 -0.767570571 -0.760981982
##  [386] -0.754393393 -0.747804805 -0.741216216 -0.734627628 -0.728039039
##  [391] -0.721450450 -0.714861862 -0.708273273 -0.701684685 -0.695096096
##  [396] -0.688507508 -0.681918919 -0.675330330 -0.668741742 -0.662153153
##  [401] -0.655564565 -0.648975976 -0.642387387 -0.635798799 -0.629210210
##  [406] -0.622621622 -0.616033033 -0.609444444 -0.602855856 -0.596267267
##  [411] -0.589678679 -0.583090090 -0.576501502 -0.569912913 -0.563324324
##  [416] -0.556735736 -0.550147147 -0.543558559 -0.536969970 -0.530381381
##  [421] -0.523792793 -0.517204204 -0.510615616 -0.504027027 -0.497438438
##  [426] -0.490849850 -0.484261261 -0.477672673 -0.471084084 -0.464495495
##  [431] -0.457906907 -0.451318318 -0.444729730 -0.438141141 -0.431552553
##  [436] -0.424963964 -0.418375375 -0.411786787 -0.405198198 -0.398609610
##  [441] -0.392021021 -0.385432432 -0.378843844 -0.372255255 -0.365666667
##  [446] -0.359078078 -0.352489489 -0.345900901 -0.339312312 -0.332723724
##  [451] -0.326135135 -0.319546547 -0.312957958 -0.306369369 -0.299780781
##  [456] -0.293192192 -0.286603604 -0.280015015 -0.273426426 -0.266837838
##  [461] -0.260249249 -0.253660661 -0.247072072 -0.240483483 -0.233894895
##  [466] -0.227306306 -0.220717718 -0.214129129 -0.207540541 -0.200951952
##  [471] -0.194363363 -0.187774775 -0.181186186 -0.174597598 -0.168009009
##  [476] -0.161420420 -0.154831832 -0.148243243 -0.141654655 -0.135066066
##  [481] -0.128477477 -0.121888889 -0.115300300 -0.108711712 -0.102123123
##  [486] -0.095534535 -0.088945946 -0.082357357 -0.075768769 -0.069180180
##  [491] -0.062591592 -0.056003003 -0.049414414 -0.042825826 -0.036237237
##  [496] -0.029648649 -0.023060060 -0.016471471 -0.009882883 -0.003294294
##  [501]  0.003294294  0.009882883  0.016471471  0.023060060  0.029648649
##  [506]  0.036237237  0.042825826  0.049414414  0.056003003  0.062591592
##  [511]  0.069180180  0.075768769  0.082357357  0.088945946  0.095534535
##  [516]  0.102123123  0.108711712  0.115300300  0.121888889  0.128477477
##  [521]  0.135066066  0.141654655  0.148243243  0.154831832  0.161420420
##  [526]  0.168009009  0.174597598  0.181186186  0.187774775  0.194363363
##  [531]  0.200951952  0.207540541  0.214129129  0.220717718  0.227306306
##  [536]  0.233894895  0.240483483  0.247072072  0.253660661  0.260249249
##  [541]  0.266837838  0.273426426  0.280015015  0.286603604  0.293192192
##  [546]  0.299780781  0.306369369  0.312957958  0.319546547  0.326135135
##  [551]  0.332723724  0.339312312  0.345900901  0.352489489  0.359078078
##  [556]  0.365666667  0.372255255  0.378843844  0.385432432  0.392021021
##  [561]  0.398609610  0.405198198  0.411786787  0.418375375  0.424963964
##  [566]  0.431552553  0.438141141  0.444729730  0.451318318  0.457906907
##  [571]  0.464495495  0.471084084  0.477672673  0.484261261  0.490849850
##  [576]  0.497438438  0.504027027  0.510615616  0.517204204  0.523792793
##  [581]  0.530381381  0.536969970  0.543558559  0.550147147  0.556735736
##  [586]  0.563324324  0.569912913  0.576501502  0.583090090  0.589678679
##  [591]  0.596267267  0.602855856  0.609444444  0.616033033  0.622621622
##  [596]  0.629210210  0.635798799  0.642387387  0.648975976  0.655564565
##  [601]  0.662153153  0.668741742  0.675330330  0.681918919  0.688507508
##  [606]  0.695096096  0.701684685  0.708273273  0.714861862  0.721450450
##  [611]  0.728039039  0.734627628  0.741216216  0.747804805  0.754393393
##  [616]  0.760981982  0.767570571  0.774159159  0.780747748  0.787336336
##  [621]  0.793924925  0.800513514  0.807102102  0.813690691  0.820279279
##  [626]  0.826867868  0.833456456  0.840045045  0.846633634  0.853222222
##  [631]  0.859810811  0.866399399  0.872987988  0.879576577  0.886165165
##  [636]  0.892753754  0.899342342  0.905930931  0.912519520  0.919108108
##  [641]  0.925696697  0.932285285  0.938873874  0.945462462  0.952051051
##  [646]  0.958639640  0.965228228  0.971816817  0.978405405  0.984993994
##  [651]  0.991582583  0.998171171  1.004759760  1.011348348  1.017936937
##  [656]  1.024525526  1.031114114  1.037702703  1.044291291  1.050879880
##  [661]  1.057468468  1.064057057  1.070645646  1.077234234  1.083822823
##  [666]  1.090411411  1.097000000  1.103588589  1.110177177  1.116765766
##  [671]  1.123354354  1.129942943  1.136531532  1.143120120  1.149708709
##  [676]  1.156297297  1.162885886  1.169474474  1.176063063  1.182651652
##  [681]  1.189240240  1.195828829  1.202417417  1.209006006  1.215594595
##  [686]  1.222183183  1.228771772  1.235360360  1.241948949  1.248537538
##  [691]  1.255126126  1.261714715  1.268303303  1.274891892  1.281480480
##  [696]  1.288069069  1.294657658  1.301246246  1.307834835  1.314423423
##  [701]  1.321012012  1.327600601  1.334189189  1.340777778  1.347366366
##  [706]  1.353954955  1.360543544  1.367132132  1.373720721  1.380309309
##  [711]  1.386897898  1.393486486  1.400075075  1.406663664  1.413252252
##  [716]  1.419840841  1.426429429  1.433018018  1.439606607  1.446195195
##  [721]  1.452783784  1.459372372  1.465960961  1.472549550  1.479138138
##  [726]  1.485726727  1.492315315  1.498903904  1.505492492  1.512081081
##  [731]  1.518669670  1.525258258  1.531846847  1.538435435  1.545024024
##  [736]  1.551612613  1.558201201  1.564789790  1.571378378  1.577966967
##  [741]  1.584555556  1.591144144  1.597732733  1.604321321  1.610909910
##  [746]  1.617498498  1.624087087  1.630675676  1.637264264  1.643852853
##  [751]  1.650441441  1.657030030  1.663618619  1.670207207  1.676795796
##  [756]  1.683384384  1.689972973  1.696561562  1.703150150  1.709738739
##  [761]  1.716327327  1.722915916  1.729504505  1.736093093  1.742681682
##  [766]  1.749270270  1.755858859  1.762447447  1.769036036  1.775624625
##  [771]  1.782213213  1.788801802  1.795390390  1.801978979  1.808567568
##  [776]  1.815156156  1.821744745  1.828333333  1.834921922  1.841510511
##  [781]  1.848099099  1.854687688  1.861276276  1.867864865  1.874453453
##  [786]  1.881042042  1.887630631  1.894219219  1.900807808  1.907396396
##  [791]  1.913984985  1.920573574  1.927162162  1.933750751  1.940339339
##  [796]  1.946927928  1.953516517  1.960105105  1.966693694  1.973282282
##  [801]  1.979870871  1.986459459  1.993048048  1.999636637  2.006225225
##  [806]  2.012813814  2.019402402  2.025990991  2.032579580  2.039168168
##  [811]  2.045756757  2.052345345  2.058933934  2.065522523  2.072111111
##  [816]  2.078699700  2.085288288  2.091876877  2.098465465  2.105054054
##  [821]  2.111642643  2.118231231  2.124819820  2.131408408  2.137996997
##  [826]  2.144585586  2.151174174  2.157762763  2.164351351  2.170939940
##  [831]  2.177528529  2.184117117  2.190705706  2.197294294  2.203882883
##  [836]  2.210471471  2.217060060  2.223648649  2.230237237  2.236825826
##  [841]  2.243414414  2.250003003  2.256591592  2.263180180  2.269768769
##  [846]  2.276357357  2.282945946  2.289534535  2.296123123  2.302711712
##  [851]  2.309300300  2.315888889  2.322477477  2.329066066  2.335654655
##  [856]  2.342243243  2.348831832  2.355420420  2.362009009  2.368597598
##  [861]  2.375186186  2.381774775  2.388363363  2.394951952  2.401540541
##  [866]  2.408129129  2.414717718  2.421306306  2.427894895  2.434483483
##  [871]  2.441072072  2.447660661  2.454249249  2.460837838  2.467426426
##  [876]  2.474015015  2.480603604  2.487192192  2.493780781  2.500369369
##  [881]  2.506957958  2.513546547  2.520135135  2.526723724  2.533312312
##  [886]  2.539900901  2.546489489  2.553078078  2.559666667  2.566255255
##  [891]  2.572843844  2.579432432  2.586021021  2.592609610  2.599198198
##  [896]  2.605786787  2.612375375  2.618963964  2.625552553  2.632141141
##  [901]  2.638729730  2.645318318  2.651906907  2.658495495  2.665084084
##  [906]  2.671672673  2.678261261  2.684849850  2.691438438  2.698027027
##  [911]  2.704615616  2.711204204  2.717792793  2.724381381  2.730969970
##  [916]  2.737558559  2.744147147  2.750735736  2.757324324  2.763912913
##  [921]  2.770501502  2.777090090  2.783678679  2.790267267  2.796855856
##  [926]  2.803444444  2.810033033  2.816621622  2.823210210  2.829798799
##  [931]  2.836387387  2.842975976  2.849564565  2.856153153  2.862741742
##  [936]  2.869330330  2.875918919  2.882507508  2.889096096  2.895684685
##  [941]  2.902273273  2.908861862  2.915450450  2.922039039  2.928627628
##  [946]  2.935216216  2.941804805  2.948393393  2.954981982  2.961570571
##  [951]  2.968159159  2.974747748  2.981336336  2.987924925  2.994513514
##  [956]  3.001102102  3.007690691  3.014279279  3.020867868  3.027456456
##  [961]  3.034045045  3.040633634  3.047222222  3.053810811  3.060399399
##  [966]  3.066987988  3.073576577  3.080165165  3.086753754  3.093342342
##  [971]  3.099930931  3.106519520  3.113108108  3.119696697  3.126285285
##  [976]  3.132873874  3.139462462  3.146051051  3.152639640  3.159228228
##  [981]  3.165816817  3.172405405  3.178993994  3.185582583  3.192171171
##  [986]  3.198759760  3.205348348  3.211936937  3.218525526  3.225114114
##  [991]  3.231702703  3.238291291  3.244879880  3.251468468  3.258057057
##  [996]  3.264645646  3.271234234  3.277822823  3.284411411  3.291000000

X ~ N (50,30)

A média é 50 e o desvio padrão é 30.

a)

Pr(X<50) =

Pr(X-media)/sigma < (50 - 50)/30 =

Pr(Z<-0/30) = Pr(z<0) = 0.5 - Pr(0<Z<0) =

0.5 - Pr(0<Z<0) = 0.5 - 0.01994 = 0.48006

pnorm(0)

pnorm(50, mean = 50, sd=30)

plotDistr(x, dnorm(x, mean=0, sd=1), cdf=FALSE, xlab="x",
          ylab="Densidade",regions=list(c(-10,0), c(0,10)),
          col=c('#78b8de', '#f2dc8d'), legend=FALSE)

b)

Pr(40<X<61) =

Pr[(40 - 50)/30<Z<(61-50/30)] =

Pr(-0,33<Z<0,37) = Pr(0<Z<0,33) + Pr(0<Z<0,37) =

pnorm(0.37) - pnorm(-0.33) = 0.2736088

plotDistr(x, dnorm(x, mean=0, sd=1), cdf=FALSE, xlab="x",
          ylab="Densidade",regions=list(c(-0.33, 0),c(0, 0.37)),
          col=c('#f2a16b', '#b2edbc'), legend=FALSE)

c)

Pr(33<X<47) =

Pr[(33 - 50)/30<Z<(47-50/30)]

Pr(-0.57<Z<-0.1) = Pr(0<Z<0.57) + Pr(0<Z<0.1) =

pnorm(0.57) - pnorm(0.1) = 0.1758333

plotDistr(x, dnorm(x, mean=0, sd=1), cdf=FALSE, xlab="x",
          ylab="Densidade",regions=list(c(0, 0.57),c(0.1, 0.57)),
          col=c('#c0ddeb', '#f5a4db'), legend=FALSE)

Y ~ N(10,15)

A média é 10 e o desvio padrão é 15.

a)

Pr(5<Y<7) =

Pr[(5 - 10)/15<Z<(7-10/15)] =

Pr(-0.33<Z<-0.2) = Pr(0<Z<0.33) + Pr(0<Z<0.2) =

pnorm(0.33) - pnorm(0.2) = 0.05004031

plotDistr(x, dnorm(x, mean=0, sd=1), cdf=FALSE, xlab="x",
          ylab="Densidade",regions=list(c(0, 0.2),c(0.2, 0.33)),
          col=c('#62f075', '#db8f88'), legend=FALSE)

b)

Pr(9.5<Y<11) =

Pr[(9.5 - 10)/15<Z<(11-10/15)] =

Pr(-0.03<Z<0.06) = Pr(0<Z<0.03) + Pr(0<Z<0.06) =

pnorm(0.06) - pnorm(-0.3) = 0.1418336

plotDistr(x, dnorm(x, mean=0, sd=1), cdf=FALSE, xlab="x",
          ylab="Densidade",regions=list(c(-0.03, 0),c(0, 0.06)),
          col=c('#babd13', '#5475eb'), legend=FALSE)

c)

Pr(Y>7.5) =

Pr(X-media)/sigma > (10 - 7.5)/15 =

Pr(Z>2.5/15) = Pr(z>0.16) = (0.16>Z>0) =

pnorm(0.16) - pnorm(0) = 0.06355946

plotDistr(x, dnorm(x, mean=0, sd=1), cdf=FALSE, xlab="x",
              ylab="Densidade",regions=list(c(0, 0.16)),
              col=c('#37e697', 'red'), legend=FALSE)

Conclusão

Concluo minha 7ª atividade de estatística após redigir este documento com todos os cálculos propostos.