Data

1. What is the demographic profile of the respondents in terms of:


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Sex

Strand

The tables above provides the distributions of respondents in terms of sex, year level, and strand. It can be seen that there are 48 females and 52 males; 25 of which are from each strand.

2. Is there a significant difference on the variables behavioral changes, college readiness, and academic performance when grouped according to:

2.1 Sex


Call:
lm(formula = `Behavioral Changes` ~ `College Readiness` + `Academic Performance`, 
    data = Data)

Coefficients:
           (Intercept)     `College Readiness`  `Academic Performance`  
                0.1190                  0.4656                  0.3849  

From this, we may deduce that the data fail to satisfy two assumptions – Linearity and Homogeneity of Variance.

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2.1.1 Sex and Behavioral Changes

Normality Test


    Shapiro-Wilk normality test

data:  Data$`Behavioral Changes`
W = 0.95905, p-value = 0.003444

Since p-value = 0.003444 < 0.05, it is conclusive that we reject the null hypothesis. That is, we cannot assume normality.

Equality of Variance

Warning in leveneTest.default(y = y, group = group, ...): group coerced to
factor.
Levene's Test for Homogeneity of Variance (center = median)
      Df F value  Pr(>F)  
group  1  5.3162 0.02324 *
      98                  
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

The p-value is less than the 0.05 level of significance. Thus, the homogeneity assumption of the variance is not met.


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# A tibble: 2 × 11
  Sex    variable             n   min   max median   iqr  mean    sd    se    ci
  <fct>  <fct>            <dbl> <dbl> <dbl>  <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 Male   Behavioral Chan…    52     1   2.4    1.8  0.25  1.70 0.349 0.048 0.097
2 Female Behavioral Chan…    48     1   3      1.7  0.8   1.70 0.458 0.066 0.133

The mean of female and male is 1.696 and 1.704, respectively.

Mann Whitney U Test

# A tibble: 1 × 6
  .y.                    n statistic    df     p method        
* <chr>              <int>     <dbl> <int> <dbl> <chr>         
1 Behavioral Changes   100    0.0226     1 0.881 Kruskal-Wallis

Based on the p-value, there is no significant difference was observed between the group pairs.

2.1.2 Sex and College Readiness

Normality Test


    Shapiro-Wilk normality test

data:  Data$`College Readiness`
W = 0.95669, p-value = 0.002351

Since p-value = 0.002351 < 0.05, it is conclusive that we reject the null hypothesis. That is, we cannot assume normality.

Equality of Variance

Warning in leveneTest.default(y = y, group = group, ...): group coerced to
factor.
Levene's Test for Homogeneity of Variance (center = median)
      Df F value Pr(>F)
group  1  0.1055  0.746
      98               

The p-value is greater than the 0.05 level of significance. Thus, the homogeneity assumption of the variance is met.

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# A tibble: 2 × 11
  Sex    variable             n   min   max median   iqr  mean    sd    se    ci
  <fct>  <fct>            <dbl> <dbl> <dbl>  <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 Male   College Readine…    52   1     2.8    1.8  0.4   1.82 0.373 0.052 0.104
2 Female College Readine…    48   1.2   3      2    0.45  1.84 0.376 0.054 0.109

The mean of female and male is 1.823 and 1.842, respectively.

Mann Whitney U Test

# A tibble: 1 × 6
  .y.                   n statistic    df     p method        
* <chr>             <int>     <dbl> <int> <dbl> <chr>         
1 College Readiness   100    0.0606     1 0.806 Kruskal-Wallis

Based on the p-value, there is no significant difference was observed between the group pairs.

2.1.3 Sex and Academic Performance

Normality Test


    Shapiro-Wilk normality test

data:  Data$`Academic Performance`
W = 0.94744, p-value = 0.000565

Since p-value = 0.000565 < 0.05, it is conclusive that we reject the null hypothesis. That is, we cannot assume normality.

Equality of Variance

Warning in leveneTest.default(y = y, group = group, ...): group coerced to
factor.
Levene's Test for Homogeneity of Variance (center = median)
      Df F value Pr(>F)
group  1   0.287 0.5933
      98               

The p-value is greater than the 0.05 level of significance. Thus, the homogeneity assumption of the variance is met.

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# A tibble: 2 × 11
  Sex    variable             n   min   max median   iqr  mean    sd    se    ci
  <fct>  <fct>            <dbl> <dbl> <dbl>  <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 Male   Academic Perfor…    52     1   3.2      2   0.4  1.92 0.357 0.05  0.099
2 Female Academic Perfor…    48     1   2.6      2   0.4  1.86 0.372 0.054 0.108

The mean of female and male is 1.919 and 1.862, respectively.

Mann Whitney U Test

# A tibble: 1 × 6
  .y.                      n statistic    df     p method        
* <chr>                <int>     <dbl> <int> <dbl> <chr>         
1 Academic Performance   100     0.239     1 0.625 Kruskal-Wallis

Based on the p-value, there is no significant difference was observed between the group pairs.

2.2 Strand

2.2.1 Strand and Behavioral Changes

Normality Test


    Shapiro-Wilk normality test

data:  Data$`Behavioral Changes`
W = 0.95905, p-value = 0.003444

Since p-value = 0.003444 < 0.05, it is conclusive that we reject the null hypothesis. That is, we cannot assume normality.

Equality of Variance

Warning in leveneTest.default(y = y, group = group, ...): group coerced to
factor.
Levene's Test for Homogeneity of Variance (center = median)
      Df F value Pr(>F)
group  3  0.2209 0.8817
      96               

The p-value is greater than the 0.05 level of significance. Thus, the homogeneity assumption of the variance is met.

Warning in plot.xy(xy.coords(x, y), type = type, ...): "frame" is not a
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Warning in axis(1, at = 1:length(means), labels = legends, ...): "frame" is not
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# A tibble: 4 × 11
  Strand variable             n   min   max median   iqr  mean    sd    se    ci
  <fct>  <fct>            <dbl> <dbl> <dbl>  <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 STEM   Behavioral Chan…    25   1.4   3      2     0.4  1.99 0.381 0.076 0.157
2 ABM    Behavioral Chan…    25   1     2.2    1.4   0.6  1.49 0.361 0.072 0.149
3 HUMSS  Behavioral Chan…    25   1     2.2    1.8   0.4  1.71 0.337 0.067 0.139
4 GAS    Behavioral Chan…    25   1     2.2    1.6   0.6  1.61 0.367 0.073 0.152

The mean of STEM, ABM, HUMSS, and GAS is 1.992, 1.488, 1.712, and 1.608, respectively.

Kruskal-wallis Test

# A tibble: 1 × 6
  .y.                    n statistic    df        p method        
* <chr>              <int>     <dbl> <int>    <dbl> <chr>         
1 Behavioral Changes   100      18.3     3 0.000389 Kruskal-Wallis

Based on the p-value, there is significant difference was observed between the group pairs.

Pairwise Comparisons

# A tibble: 6 × 9
  .y.           group1 group2    n1    n2 statistic       p   p.adj p.adj.signif
* <chr>         <chr>  <chr>  <int> <int>     <dbl>   <dbl>   <dbl> <chr>       
1 Behavioral C… STEM   ABM       25    25    -4.11  3.89e-5 2.33e-4 ***         
2 Behavioral C… STEM   HUMSS     25    25    -2.11  3.52e-2 2.11e-1 ns          
3 Behavioral C… STEM   GAS       25    25    -3.02  2.57e-3 1.54e-2 *           
4 Behavioral C… ABM    HUMSS     25    25     2.01  4.47e-2 2.68e-1 ns          
5 Behavioral C… ABM    GAS       25    25     1.10  2.72e-1 1   e+0 ns          
6 Behavioral C… HUMSS  GAS       25    25    -0.909 3.64e-1 1   e+0 ns          

There is significant difference on the first four group pairs.

2.2.2 Strand and College Readiness

Normality Test


    Shapiro-Wilk normality test

data:  Data$`College Readiness`
W = 0.95669, p-value = 0.002351

Since p-value = 0.002351 < 0.05, it is conclusive that we reject the null hypothesis. That is, we cannot assume normality.

Equality of Variance

Warning in leveneTest.default(y = y, group = group, ...): group coerced to
factor.
Levene's Test for Homogeneity of Variance (center = median)
      Df F value Pr(>F)
group  3  0.6172 0.6055
      96               

The p-value is greater than the 0.05 level of significance. Thus, the homogeneity assumption of the variance is met.

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# A tibble: 4 × 11
  Strand variable             n   min   max median   iqr  mean    sd    se    ci
  <fct>  <fct>            <dbl> <dbl> <dbl>  <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 STEM   College Readine…    25   1.2   3      2     0.6  1.94 0.398 0.08  0.164
2 ABM    College Readine…    25   1.2   2.6    1.6   0.4  1.73 0.326 0.065 0.135
3 HUMSS  College Readine…    25   1     2.6    2     0.4  1.88 0.351 0.07  0.145
4 GAS    College Readine…    25   1     2.8    1.8   0.4  1.78 0.393 0.079 0.162

The mean of STEM, ABM, HUMSS, and GAS is 1.994, 1.728, 1.880, and 1.776, respectively.

Kruskal-wallis Test

# A tibble: 1 × 6
  .y.                   n statistic    df     p method        
* <chr>             <int>     <dbl> <int> <dbl> <chr>         
1 College Readiness   100      6.24     3 0.101 Kruskal-Wallis

Based on the p-value, there is no significant difference was observed between the group pairs.

Pairwise Comparisons

# A tibble: 6 × 9
  .y.              group1 group2    n1    n2 statistic      p p.adj p.adj.signif
* <chr>            <chr>  <chr>  <int> <int>     <dbl>  <dbl> <dbl> <chr>       
1 College Readine… STEM   ABM       25    25    -2.16  0.0306 0.184 ns          
2 College Readine… STEM   HUMSS     25    25    -0.333 0.739  1     ns          
3 College Readine… STEM   GAS       25    25    -1.57  0.116  0.698 ns          
4 College Readine… ABM    HUMSS     25    25     1.83  0.0674 0.405 ns          
5 College Readine… ABM    GAS       25    25     0.591 0.554  1     ns          
6 College Readine… HUMSS  GAS       25    25    -1.24  0.216  1     ns          

There is significant difference between STEM and ABM.

2.2.3 Strand and Academic Performance

Normality Test


    Shapiro-Wilk normality test

data:  Data$`Academic Performance`
W = 0.94744, p-value = 0.000565

Since p-value = 0.000565 < 0.05, it is conclusive that we reject the null hypothesis. That is, we cannot assume normality.

Equality of Variance

Warning in leveneTest.default(y = y, group = group, ...): group coerced to
factor.
Levene's Test for Homogeneity of Variance (center = median)
      Df F value Pr(>F)
group  3  0.4868 0.6923
      96               

The p-value is greater than the 0.05 level of significance. Thus, the homogeneity assumption of the variance is met.

Warning in plot.xy(xy.coords(x, y), type = type, ...): "frame" is not a
graphical parameter
Warning in axis(1, at = 1:length(means), labels = legends, ...): "frame" is not
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# A tibble: 4 × 11
  Strand variable             n   min   max median   iqr  mean    sd    se    ci
  <fct>  <fct>            <dbl> <dbl> <dbl>  <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 STEM   Academic Perfor…    25   1.2   3.2    2     0.4  2.03 0.435 0.087 0.179
2 ABM    Academic Perfor…    25   1     2.4    1.8   0.4  1.81 0.358 0.072 0.148
3 HUMSS  Academic Perfor…    25   1.4   2.6    2     0.2  1.93 0.294 0.059 0.121
4 GAS    Academic Perfor…    25   1     2.4    1.8   0.4  1.8  0.321 0.064 0.133

The mean of STEM, ABM, HUMSS, and GAS is 2.032, 1.808, 1.928, and 1.800, respectively.

Kruskal-wallis Test

# A tibble: 1 × 6
  .y.                      n statistic    df     p method        
* <chr>                <int>     <dbl> <int> <dbl> <chr>         
1 Academic Performance   100      5.61     3 0.132 Kruskal-Wallis

Based on the p-value, there is no significant difference was observed between the group pairs.

Pairwise Comparisons

# A tibble: 6 × 9
  .y.              group1 group2    n1    n2 statistic      p p.adj p.adj.signif
* <chr>            <chr>  <chr>  <int> <int>     <dbl>  <dbl> <dbl> <chr>       
1 Academic Perfor… STEM   ABM       25    25    -1.89  0.0594 0.356 ns          
2 Academic Perfor… STEM   HUMSS     25    25    -0.809 0.419  1     ns          
3 Academic Perfor… STEM   GAS       25    25    -2.06  0.0391 0.235 ns          
4 Academic Perfor… ABM    HUMSS     25    25     1.08  0.282  1     ns          
5 Academic Perfor… ABM    GAS       25    25    -0.178 0.859  1     ns          
6 Academic Perfor… HUMSS  GAS       25    25    -1.25  0.210  1     ns          

There is significant difference between STEM and GAS.

3. Is there a significant relationship between behavioral changes, college readiness, and academic performance?

Normality Test


    Shapiro-Wilk normality test

data:  Data1$Scores
W = 0.96224, p-value = 4.934e-07

Since p-value = 4.934e-07 < 0.05, it is conclusive that we reject the null hypothesis. That is, we cannot assume normality.

Equality of Variance

Warning in leveneTest.default(y = y, group = group, ...): group coerced to
factor.
Levene's Test for Homogeneity of Variance (center = median)
       Df F value Pr(>F)
group   2  1.3236 0.2677
      297               

The p-value is greater than the 0.05 level of significance. Thus, the homogeneity assumption of the variance is met.

Warning in plot.xy(xy.coords(x, y), type = type, ...): "frame" is not a
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Warning in axis(1, at = 1:length(means), labels = legends, ...): "frame" is not
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# A tibble: 3 × 11
  Variables      variable     n   min   max median   iqr  mean    sd    se    ci
  <fct>          <fct>    <dbl> <dbl> <dbl>  <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 Behavioral Ch… Scores     100     1   3      1.8   0.6  1.7  0.403 0.04  0.08 
2 College Readi… Scores     100     1   3      1.8   0.4  1.83 0.373 0.037 0.074
3 Academic Perf… Scores     100     1   3.2    2     0.4  1.89 0.363 0.036 0.072

The mean of Behavioral Changes, College Readiness, and Academic Performance is 1.700, 1.832, and 1.892, respectively.

Kruskal-wallis Test

# A tibble: 1 × 6
  .y.        n statistic    df       p method        
* <chr>  <int>     <dbl> <int>   <dbl> <chr>         
1 Scores   300      12.7     2 0.00176 Kruskal-Wallis

Based on the p-value, there is significant difference was observed between the group pairs.

Pairwise Comparisons

# A tibble: 3 × 9
  .y.    group1        group2    n1    n2 statistic       p   p.adj p.adj.signif
* <chr>  <chr>         <chr>  <int> <int>     <dbl>   <dbl>   <dbl> <chr>       
1 Scores Behavioral C… Colle…   100   100      2.27 2.32e-2 0.0695  ns          
2 Scores Behavioral C… Acade…   100   100      3.51 4.45e-4 0.00134 **          
3 Scores College Read… Acade…   100   100      1.24 2.14e-1 0.643   ns          

There is significant performance between behavioral changes and college readiness so with behavioral changes and academic performance.

4. On which variable does additional two year program on career development for SHS have the most significant impact?

Based on the provided output above, we can say that it is the academic performance.