In-Class Exercise 1: Chapter 4 of Lattice

Load data file

##       Rural Male Rural Female Urban Male Urban Female
## 50-54       11.7          8.7       15.4          8.4
## 55-59       18.1         11.7       24.3         13.6
## 60-64       26.9         20.3       37.0         19.3
## 65-69       41.0         30.9       54.6         35.1
## 70-74       66.0         54.3       71.1         50.0
## [1] "matrix"

Show the methods of dotplot in lattice package

## [1] dotplot.array*   dotplot.default* dotplot.formula* dotplot.matrix* 
## [5] dotplot.numeric* dotplot.table*  
## see '?methods' for accessing help and source code

Plot the dotplot of death rates for the different age by people

In-Class Exercise 2: The Reading scores for the Student-Teacher ratio

Load data file

##   distcod  county                        district grspan enrltot teachers
## 1   75119 Alameda              Sunol Glen Unified  KK-08     195    10.90
## 2   61499   Butte            Manzanita Elementary  KK-08     240    11.15
## 3   61549   Butte     Thermalito Union Elementary  KK-08    1550    82.90
## 4   61457   Butte Golden Feather Union Elementary  KK-08     243    14.00
## 5   61523   Butte        Palermo Union Elementary  KK-08    1335    71.50
## 6   62042  Fresno         Burrel Union Elementary  KK-08     137     6.40
##   calwpct mealpct computer testscr   compstu  expnstu      str    avginc
## 1  0.5102  2.0408       67  690.80 0.3435898 6384.911 17.88991 22.690001
## 2 15.4167 47.9167      101  661.20 0.4208333 5099.381 21.52466  9.824000
## 3 55.0323 76.3226      169  643.60 0.1090323 5501.955 18.69723  8.978000
## 4 36.4754 77.0492       85  647.70 0.3497942 7101.831 17.35714  8.978000
## 5 33.1086 78.4270      171  640.85 0.1280899 5235.988 18.67133  9.080333
## 6 12.3188 86.9565       25  605.55 0.1824818 5580.147 21.40625 10.415000
##       elpct readscr mathscr
## 1  0.000000   691.6   690.0
## 2  4.583333   660.5   661.9
## 3 30.000002   636.3   650.9
## 4  0.000000   651.9   643.5
## 5 13.857677   641.8   639.9
## 6 12.408759   605.7   605.4

Create a new variable of student-teacher ratio

In fact, The raw data set have been existed a str variable which is same as new variable I was created.

##   distcod  county                        district grspan enrltot teachers
## 1   75119 Alameda              Sunol Glen Unified  KK-08     195    10.90
## 2   61499   Butte            Manzanita Elementary  KK-08     240    11.15
## 3   61549   Butte     Thermalito Union Elementary  KK-08    1550    82.90
## 4   61457   Butte Golden Feather Union Elementary  KK-08     243    14.00
## 5   61523   Butte        Palermo Union Elementary  KK-08    1335    71.50
## 6   62042  Fresno         Burrel Union Elementary  KK-08     137     6.40
##   calwpct mealpct computer testscr   compstu  expnstu      str    avginc
## 1  0.5102  2.0408       67  690.80 0.3435898 6384.911 17.88991 22.690001
## 2 15.4167 47.9167      101  661.20 0.4208333 5099.381 21.52466  9.824000
## 3 55.0323 76.3226      169  643.60 0.1090323 5501.955 18.69723  8.978000
## 4 36.4754 77.0492       85  647.70 0.3497942 7101.831 17.35714  8.978000
## 5 33.1086 78.4270      171  640.85 0.1280899 5235.988 18.67133  9.080333
## 6 12.3188 86.9565       25  605.55 0.1824818 5580.147 21.40625 10.415000
##       elpct readscr mathscr     ST_R
## 1  0.000000   691.6   690.0 17.88991
## 2  4.583333   660.5   661.9 21.52466
## 3 30.000002   636.3   650.9 18.69723
## 4  0.000000   651.9   643.5 17.35714
## 5 13.857677   641.8   639.9 18.67133
## 6 12.408759   605.7   605.4 21.40625

Divide the reading scores into three parts

Filter grspan == KK-08

## ─ Attaching packages ────────────────────────── tidyverse 1.3.0 ─
## ✓ ggplot2 3.2.1     ✓ purrr   0.3.3
## ✓ tibble  2.1.3     ✓ dplyr   0.8.4
## ✓ tidyr   1.0.2     ✓ stringr 1.4.0
## ✓ readr   1.3.1     ✓ forcats 0.4.0
## ─ Conflicts ─────────────────────────── tidyverse_conflicts() ─
## x dplyr::filter() masks stats::filter()
## x dplyr::lag()    masks stats::lag()

Plot the reading scores for the student-teacher ratio by different level of reading socres

In-Class Exercise 3:

Load data file

##   eval     beauty sex age minority tenure courseID
## 1  4.3  0.2015666   1  36        1      0        3
## 2  4.5 -0.8260813   0  59        0      1        0
## 3  3.7 -0.6603327   0  51        0      1        4
## 4  4.3 -0.7663125   1  40        0      1        2
## 5  4.4  1.4214450   1  31        0      0        0
## 6  4.2  0.5002196   0  62        0      1        0

Show the details of the data

## 'data.frame':    463 obs. of  7 variables:
##  $ eval    : num  4.3 4.5 3.7 4.3 4.4 4.2 4 3.4 4.5 3.9 ...
##  $ beauty  : num  0.202 -0.826 -0.66 -0.766 1.421 ...
##  $ sex     : int  1 0 0 1 1 0 1 1 1 0 ...
##  $ age     : int  36 59 51 40 31 62 33 51 33 47 ...
##  $ minority: int  1 0 0 0 0 0 0 0 0 0 ...
##  $ tenure  : int  0 1 1 1 0 1 0 1 0 0 ...
##  $ courseID: int  3 0 4 2 0 0 4 0 0 4 ...

In-Class Exercise 4: Brain Size and IQ

Load data file

##   Sbj Gender FSIQ VIQ PIQ Weight Height MRICount
## 1   1 Female  133 132 124    118   64.5   816932
## 2   2   Male  140 150 124     NA   72.5  1001121
## 3   3   Male  139 123 150    143   73.3  1038437
## 4   4   Male  133 129 128    172   68.8   965353
## 5   5 Female  137 132 134    147   65.0   951545
## 6   6 Female   99  90 110    146   69.0   928799

Transform the different type of IQ from wide to long format

## 
## Attaching package: 'reshape'
## The following object is masked from 'package:dplyr':
## 
##     rename
## The following objects are masked from 'package:tidyr':
## 
##     expand, smiths

Q: Are there gender differences in the three IQ scores?

## A: Yes, in our visual inspection, but specificially in FSIQ (small effect), VIQ (large effect), not in PIQ (no effect).

Q: Is the relationship between height and weight gender dependent?

## A: Yes, in our visual inspection, gender modulate the weight and height.

Q: Is the relationship between IQ and brainsize (as measured by MRIcount) gender dependent?

## A: Because I couldn’t observe the significant pattern in the figure, I conducted linear regression model to examine the gender effect.

## 
## Call:
## lm(formula = FSIQ ~ MRICount + Gender, data = dta)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -31.410 -20.011   0.924  21.978  36.094 
## 
## Coefficients:
##               Estimate Std. Error t value Pr(>|t|)   
## (Intercept) -4.371e+01  5.644e+01  -0.774  0.44358   
## MRICount     1.804e-04  6.516e-05   2.768  0.00876 **
## GenderMale  -1.353e+01  9.302e+00  -1.455  0.15418   
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 22.46 on 37 degrees of freedom
## Multiple R-squared:  0.1751, Adjusted R-squared:  0.1305 
## F-statistic: 3.927 on 2 and 37 DF,  p-value: 0.02842

The results revealed that no gender effect on Brain size to FSIQ

## 
## Call:
## lm(formula = VIQ ~ MRICount + Gender, data = dta)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -38.840 -18.429  -1.268  17.487  35.537 
## 
## Coefficients:
##               Estimate Std. Error t value Pr(>|t|)  
## (Intercept) -1.491e+01  5.687e+01  -0.262   0.7946  
## MRICount     1.442e-04  6.567e-05   2.195   0.0345 *
## GenderMale  -7.492e+00  9.374e+00  -0.799   0.4293  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 22.63 on 37 degrees of freedom
## Multiple R-squared:  0.1289, Adjusted R-squared:  0.08184 
## F-statistic: 2.738 on 2 and 37 DF,  p-value: 0.0778

The results revealed that no gender effect on Brain size to VIQ

## 
## Call:
## lm(formula = PIQ ~ MRICount + Gender, data = dta)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -32.696 -15.155  -6.259  16.898  37.771 
## 
## Coefficients:
##               Estimate Std. Error t value Pr(>|t|)   
## (Intercept) -5.985e+01  5.069e+01  -1.181  0.24530   
## MRICount     1.974e-04  5.853e-05   3.373  0.00176 **
## GenderMale  -1.705e+01  8.355e+00  -2.041  0.04844 * 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 20.17 on 37 degrees of freedom
## Multiple R-squared:  0.2357, Adjusted R-squared:  0.1944 
## F-statistic: 5.704 on 2 and 37 DF,  p-value: 0.006929

The results revealed that there is a gender effect on Brain size to PIQ