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September 12, 2018 17:49
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Fitting model in TFP where I try to 'randomize' the fixed coefficients
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{ | |
"cells": [ | |
{ | |
"cell_type": "code", | |
"execution_count": 1, | |
"metadata": {}, | |
"outputs": [], | |
"source": [ | |
"%%capture \n", | |
"\n", | |
"%matplotlib inline\n", | |
"\n", | |
"import IPython\n", | |
"import matplotlib.pyplot as plt\n", | |
"import numpy as np\n", | |
"import pandas as pd\n", | |
"import requests\n", | |
"import tensorflow as tf\n", | |
"import tensorflow_probability as tfp\n", | |
"import warnings\n", | |
"\n", | |
"from tensorflow_probability import edward2 as ed\n", | |
"tfd = tfp.distributions\n", | |
"\n", | |
"from keras.constraints import non_neg\n", | |
"\n", | |
"import statsmodels.api as sm\n", | |
"import statsmodels.formula.api as smf\n", | |
" \n", | |
"plt.style.use('ggplot')" | |
] | |
}, | |
{ | |
"cell_type": "code", | |
"execution_count": 2, | |
"metadata": {}, | |
"outputs": [ | |
{ | |
"data": { | |
"text/html": [ | |
"<div>\n", | |
"<style scoped>\n", | |
" .dataframe tbody tr th:only-of-type {\n", | |
" vertical-align: middle;\n", | |
" }\n", | |
"\n", | |
" .dataframe tbody tr th {\n", | |
" vertical-align: top;\n", | |
" }\n", | |
"\n", | |
" .dataframe thead th {\n", | |
" text-align: right;\n", | |
" }\n", | |
"</style>\n", | |
"<table border=\"1\" class=\"dataframe\">\n", | |
" <thead>\n", | |
" <tr style=\"text-align: right;\">\n", | |
" <th></th>\n", | |
" <th>iso3</th>\n", | |
" <th>year</th>\n", | |
" <th>ln_gdppc</th>\n", | |
" <th>ln_TFR</th>\n", | |
" <th>ln_pop</th>\n", | |
" <th>intercept</th>\n", | |
" </tr>\n", | |
" </thead>\n", | |
" <tbody>\n", | |
" <tr>\n", | |
" <th>0</th>\n", | |
" <td>0</td>\n", | |
" <td>1960</td>\n", | |
" <td>7.626012</td>\n", | |
" <td>2.008214</td>\n", | |
" <td>16.012330</td>\n", | |
" <td>1.0</td>\n", | |
" </tr>\n", | |
" <tr>\n", | |
" <th>1</th>\n", | |
" <td>0</td>\n", | |
" <td>1961</td>\n", | |
" <td>7.613911</td>\n", | |
" <td>2.008214</td>\n", | |
" <td>16.031095</td>\n", | |
" <td>1.0</td>\n", | |
" </tr>\n", | |
" <tr>\n", | |
" <th>2</th>\n", | |
" <td>0</td>\n", | |
" <td>1962</td>\n", | |
" <td>7.610066</td>\n", | |
" <td>2.008214</td>\n", | |
" <td>16.050445</td>\n", | |
" <td>1.0</td>\n", | |
" </tr>\n", | |
" <tr>\n", | |
" <th>3</th>\n", | |
" <td>0</td>\n", | |
" <td>1963</td>\n", | |
" <td>7.607401</td>\n", | |
" <td>2.008214</td>\n", | |
" <td>16.070370</td>\n", | |
" <td>1.0</td>\n", | |
" </tr>\n", | |
" <tr>\n", | |
" <th>4</th>\n", | |
" <td>0</td>\n", | |
" <td>1964</td>\n", | |
" <td>7.603515</td>\n", | |
" <td>2.008214</td>\n", | |
" <td>16.090864</td>\n", | |
" <td>1.0</td>\n", | |
" </tr>\n", | |
" </tbody>\n", | |
"</table>\n", | |
"</div>" | |
], | |
"text/plain": [ | |
" iso3 year ln_gdppc ln_TFR ln_pop intercept\n", | |
"0 0 1960 7.626012 2.008214 16.012330 1.0\n", | |
"1 0 1961 7.613911 2.008214 16.031095 1.0\n", | |
"2 0 1962 7.610066 2.008214 16.050445 1.0\n", | |
"3 0 1963 7.607401 2.008214 16.070370 1.0\n", | |
"4 0 1964 7.603515 2.008214 16.090864 1.0" | |
] | |
}, | |
"execution_count": 2, | |
"metadata": {}, | |
"output_type": "execute_result" | |
} | |
], | |
"source": [ | |
"## Get GDP data for testing\n", | |
"data = pd.read_csv('/home/j/Project/IRH/Forecasting/gdp/data/RT_2018_GDP_use.csv')\n", | |
"\n", | |
"## Prep data\n", | |
"data = data[['iso3', 'year', 'ln_gdppc', 'ln_TFR', 'ln_pop']]\n", | |
"data['intercept'] = 1.\n", | |
"data = data.dropna()\n", | |
"\n", | |
"# Remap categories to start from 0 and end at max(category).\n", | |
"data['iso3'] = data['iso3'].astype('category').cat.codes\n", | |
"\n", | |
"## Number of REs\n", | |
"n_res = max(data.iso3) + 1\n", | |
"\n", | |
"data.head()" | |
] | |
}, | |
{ | |
"cell_type": "markdown", | |
"metadata": {}, | |
"source": [ | |
"### Model:\n", | |
"$$ ln(GDPpc) = \\alpha + \\alpha_i + \\beta \\ln(TFR) + \\epsilon_{i,t} $$ \n", | |
"$$ \\epsilon_{i,t} \\sim \\mathcal{N}(0, \\sigma^2) $$ \n", | |
"$$ \\alpha_i \\sim \\mathcal{N}(0, \\sigma_a^2) $$\n" | |
] | |
}, | |
{ | |
"cell_type": "code", | |
"execution_count": 3, | |
"metadata": { | |
"scrolled": true | |
}, | |
"outputs": [ | |
{ | |
"data": { | |
"text/html": [ | |
"<table class=\"simpletable\">\n", | |
"<tr>\n", | |
" <td>Model:</td> <td>MixedLM</td> <td>Dependent Variable:</td> <td>ln_gdppc</td> \n", | |
"</tr>\n", | |
"<tr>\n", | |
" <td>No. Observations:</td> <td>11700</td> <td>Method:</td> <td>REML</td> \n", | |
"</tr>\n", | |
"<tr>\n", | |
" <td>No. Groups:</td> <td>195</td> <td>Scale:</td> <td>0.1200</td> \n", | |
"</tr>\n", | |
"<tr>\n", | |
" <td>Min. group size:</td> <td>60</td> <td>Likelihood:</td> <td>-4798.2007</td>\n", | |
"</tr>\n", | |
"<tr>\n", | |
" <td>Max. group size:</td> <td>60</td> <td>Converged:</td> <td>Yes</td> \n", | |
"</tr>\n", | |
"<tr>\n", | |
" <td>Mean group size:</td> <td>60.0</td> <td></td> <td></td> \n", | |
"</tr>\n", | |
"</table>\n", | |
"<table class=\"simpletable\">\n", | |
"<tr>\n", | |
" <td></td> <th>Coef.</th> <th>Std.Err.</th> <th>z</th> <th>P>|z|</th> <th>[0.025</th> <th>0.975]</th>\n", | |
"</tr>\n", | |
"<tr>\n", | |
" <th>Intercept</th> <td>9.929</td> <td>0.070</td> <td>142.555</td> <td>0.000</td> <td>9.793</td> <td>10.066</td>\n", | |
"</tr>\n", | |
"<tr>\n", | |
" <th>ln_TFR</th> <td>-0.876</td> <td>0.011</td> <td>-82.073</td> <td>0.000</td> <td>-0.897</td> <td>-0.855</td>\n", | |
"</tr>\n", | |
"<tr>\n", | |
" <th>Group Var</th> <td>0.909</td> <td>0.270</td> <td></td> <td></td> <td></td> <td></td> \n", | |
"</tr>\n", | |
"</table>" | |
], | |
"text/plain": [ | |
"<class 'statsmodels.iolib.summary2.Summary'>\n", | |
"\"\"\"\n", | |
" Mixed Linear Model Regression Results\n", | |
"========================================================\n", | |
"Model: MixedLM Dependent Variable: ln_gdppc \n", | |
"No. Observations: 11700 Method: REML \n", | |
"No. Groups: 195 Scale: 0.1200 \n", | |
"Min. group size: 60 Likelihood: -4798.2007\n", | |
"Max. group size: 60 Converged: Yes \n", | |
"Mean group size: 60.0 \n", | |
"--------------------------------------------------------\n", | |
" Coef. Std.Err. z P>|z| [0.025 0.975]\n", | |
"--------------------------------------------------------\n", | |
"Intercept 9.929 0.070 142.555 0.000 9.793 10.066\n", | |
"ln_TFR -0.876 0.011 -82.073 0.000 -0.897 -0.855\n", | |
"Group Var 0.909 0.270 \n", | |
"========================================================\n", | |
"\n", | |
"\"\"\"" | |
] | |
}, | |
"execution_count": 3, | |
"metadata": {}, | |
"output_type": "execute_result" | |
} | |
], | |
"source": [ | |
"## Fit in StatsModels first\n", | |
"md = smf.mixedlm(\"ln_gdppc ~ 1 + ln_TFR\", data, groups=data[\"iso3\"])\n", | |
"sm_fit = md.fit() \n", | |
"sm_fit.summary()" | |
] | |
}, | |
{ | |
"cell_type": "code", | |
"execution_count": 4, | |
"metadata": {}, | |
"outputs": [], | |
"source": [ | |
"## Get the data for 'features' and 'labels' (xvars and yvar)\n", | |
"get_value = lambda dataframe, key, dtype: dataframe[key].values.astype(dtype)\n", | |
"\n", | |
"## We get the country codes as integers and then attach on the fixed effects\n", | |
"features_train = {\n", | |
" k: get_value(data, key=k, dtype=np.int32)\n", | |
" for k in ['iso3']}\n", | |
"features_train.update({\n", | |
" k: get_value(data, key=k, dtype=np.float64)\n", | |
" for k in ['intercept', 'ln_TFR']})\n", | |
"\n", | |
"## Get yvar\n", | |
"labels_train = get_value(data, key='ln_gdppc', dtype=np.float64)" | |
] | |
}, | |
{ | |
"cell_type": "markdown", | |
"metadata": {}, | |
"source": [ | |
"### Define our mixed effects model, returning the prediction for TFR coefficient converted to a 'random' variable" | |
] | |
}, | |
{ | |
"cell_type": "code", | |
"execution_count": 19, | |
"metadata": {}, | |
"outputs": [], | |
"source": [ | |
"## Using Random TFR (with a meh prior)\n", | |
"def linear_mixed_effects_model_randomTFR(features):\n", | |
" \n", | |
" # Set up fixed effects and other parameters.\n", | |
" intercept = tf.get_variable(\"intercept\", []) # alpha in eq\n", | |
" effect_ln_TFR = ed.Normal(loc = tf.zeros(1), scale = tf.ones(1), name = \"effect_ln_TFR\") \n", | |
" \n", | |
" ## The two variances (exp to force positive estimate)\n", | |
" stddev_iso3 = tf.exp(tf.get_variable(\"stddev_iso3\", [])) \n", | |
" model_stddev = tf.exp(tf.get_variable(\"model_stddev\", []))\n", | |
" \n", | |
" ## Set up random effects.\n", | |
" effect_iso3 = ed.MultivariateNormalDiag( \n", | |
" loc=tf.zeros(n_res),\n", | |
" scale_identity_multiplier=stddev_iso3,\n", | |
" name=\"effect_iso3\")\n", | |
" \n", | |
" ## Likelihood\n", | |
" ln_gdppc = ed.Normal(\n", | |
" loc=((intercept * features['intercept']) +\n", | |
" (effect_ln_TFR * features[\"ln_TFR\"]) + \n", | |
" tf.gather(effect_iso3, features[\"iso3\"])),\n", | |
" scale=model_stddev, name=\"ln_gdppc\")\n", | |
" return ln_gdppc\n" | |
] | |
}, | |
{ | |
"cell_type": "code", | |
"execution_count": 20, | |
"metadata": {}, | |
"outputs": [], | |
"source": [ | |
"# Unnormalized target density as a function of states of REs.\n", | |
"def target_log_prob_fn_randomTFR(effect_iso3, effect_ln_TFR): \n", | |
" return log_joint(\n", | |
" features=features_train,\n", | |
" effect_iso3=effect_iso3, \n", | |
" effect_ln_TFR=effect_ln_TFR,\n", | |
" ln_gdppc=labels_train)" | |
] | |
}, | |
{ | |
"cell_type": "markdown", | |
"metadata": {}, | |
"source": [ | |
"### EM and optimization" | |
] | |
}, | |
{ | |
"cell_type": "code", | |
"execution_count": 21, | |
"metadata": {}, | |
"outputs": [], | |
"source": [ | |
"tf.reset_default_graph()\n", | |
"model_template = tf.make_template(\"model\", linear_mixed_effects_model_randomTFR)\n", | |
"\n", | |
"## Make joint LL\n", | |
"log_joint = ed.make_log_joint_fn(model_template)\n", | |
"\n", | |
"## Set up E-step (MCMC) for RE vars\n", | |
"effect_iso3 = tf.get_variable(\"effect_iso3\", [n_res], trainable=False)\n", | |
"effect_ln_TFR = tf.get_variable(\"effect_ln_TFR\", [1], trainable=False)\n", | |
"\n", | |
"## Global step variable holder\n", | |
"global_step = tf.Variable(0, trainable=False, name=\"global_step\")\n", | |
"\n", | |
"## Set up MCMC object\n", | |
"hmc = tfp.mcmc.HamiltonianMonteCarlo(\n", | |
" target_log_prob_fn=target_log_prob_fn_randomTFR,\n", | |
" step_size=0.02,\n", | |
" num_leapfrog_steps=2)\n", | |
"\n", | |
"## RE state to update\n", | |
"current_state = [effect_iso3, effect_ln_TFR]\n", | |
"\n", | |
"## Update state\n", | |
"with warnings.catch_warnings():\n", | |
" warnings.simplefilter(\"ignore\")\n", | |
" next_state, kernel_results = hmc.one_step(current_state=current_state,\n", | |
" previous_kernel_results=hmc.bootstrap_results(current_state))\n", | |
"\n", | |
"## Update Expectation\n", | |
"expectation_update = tf.group(effect_iso3.assign(next_state[0]),\\\n", | |
" effect_ln_TFR.assign(next_state[1]))\n", | |
"\n", | |
"\n", | |
"# Set up M-step (gradient descent), using Adam Optimizer\n", | |
"with tf.control_dependencies([expectation_update]):\n", | |
" loss = -target_log_prob_fn_randomTFR(effect_iso3, effect_ln_TFR) \n", | |
" learning_rate = tf.train.exponential_decay(learning_rate=0.01, \n", | |
" global_step=global_step,\n", | |
" decay_steps=20, \n", | |
" decay_rate=0.90, staircase=True)\n", | |
" optimizer = tf.train.AdamOptimizer(learning_rate=learning_rate)\n", | |
" minimization_update = optimizer.minimize(loss)" | |
] | |
}, | |
{ | |
"cell_type": "code", | |
"execution_count": 22, | |
"metadata": {}, | |
"outputs": [ | |
{ | |
"name": "stdout", | |
"output_type": "stream", | |
"text": [ | |
"Warm-Up Iteration: 0 Acceptance Rate: 1.000\n", | |
"Warm-Up Iteration: 250 Acceptance Rate: 0.466\n", | |
"Warm-Up Iteration: 499 Acceptance Rate: 0.414\n", | |
"Iteration: 0 Loss: 23264.594,ln_TFR:4.226, intercept:0.601\n", | |
"Iteration: 10 Loss: 21832.441,ln_TFR:3.764, intercept:1.088\n", | |
"Iteration: 20 Loss: 20732.273,ln_TFR:3.336, intercept:1.546\n", | |
"Iteration: 30 Loss: 20502.531,ln_TFR:3.293, intercept:1.797\n", | |
"Iteration: 40 Loss: 20492.750,ln_TFR:3.293, intercept:1.786\n", | |
"Iteration: 50 Loss: 20489.379,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 60 Loss: 20488.174,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 70 Loss: 20487.762,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 80 Loss: 20487.631,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 90 Loss: 20487.594,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 100 Loss: 20487.580,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 110 Loss: 20487.578,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 120 Loss: 20487.580,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 130 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 140 Loss: 20487.578,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 150 Loss: 20487.578,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 160 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 170 Loss: 20487.578,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 180 Loss: 20487.578,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 190 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 200 Loss: 20487.578,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 210 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 220 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 230 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 240 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 250 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 260 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 270 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 280 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 290 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 300 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 310 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 320 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 330 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 340 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 350 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 360 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 370 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 380 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 390 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 400 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 410 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 420 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 430 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 440 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 450 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 460 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 470 Loss: 20487.578,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 480 Loss: 20487.576,ln_TFR:3.293, intercept:1.787\n", | |
"Iteration: 490 Loss: 20487.578,ln_TFR:3.293, intercept:1.787\n", | |
"CPU times: user 7min 33s, sys: 20min 30s, total: 28min 3s\n", | |
"Wall time: 32.5 s\n" | |
] | |
} | |
], | |
"source": [ | |
"%%time\n", | |
"\n", | |
"num_warmup_iters = 500\n", | |
"num_iters = 500\n", | |
"num_accepted = 0\n", | |
"\n", | |
"## Record samples of the fitted params and the loss\n", | |
"effect_iso3_samples = np.zeros([num_iters, n_res])\n", | |
"effect_ln_TFR_samples = np.zeros([num_iters])\n", | |
"effect_int_samples = np.zeros([num_iters]) \n", | |
"loss_history = np.zeros([num_iters])\n", | |
"\n", | |
"## Push fixed effects into scope so that we can record them \n", | |
"## (by default, only the REs get recorded since they're in the state)\n", | |
"with tf.variable_scope('model', reuse=True):\n", | |
" int_wghts = tf.get_variable(name='intercept', dtype=np.float32) \n", | |
"\n", | |
"## Start our sesh\n", | |
"with tf.Session() as sess:\n", | |
" sess.run(tf.global_variables_initializer())\n", | |
"\n", | |
" # Run warm-up stage.\n", | |
" for t in range(num_warmup_iters):\n", | |
" _, is_accepted_val = sess.run(\n", | |
" [expectation_update, kernel_results.is_accepted])\n", | |
" num_accepted += is_accepted_val\n", | |
" if t % 250 == 0 or t == num_warmup_iters - 1:\n", | |
" print(\"Warm-Up Iteration: {:>3} Acceptance Rate: {:.3f}\".format(\n", | |
" t, num_accepted / (t + 1)))\n", | |
"\n", | |
" num_accepted = 0 # reset acceptance rate counter\n", | |
"\n", | |
" # Run iterations (no convergence criteria)\n", | |
" for t in range(num_iters):\n", | |
" for _ in range(5): # run 5 MCMC iterations before every joint EM update\n", | |
" _ = sess.run(expectation_update)\n", | |
" [\n", | |
" _,\n", | |
" _,\n", | |
" effect_iso3_val,\n", | |
" ln_tfr_val, \n", | |
" int_val,\n", | |
" is_accepted_val,\n", | |
" loss_val,\n", | |
" ] = sess.run([\n", | |
" expectation_update,\n", | |
" minimization_update,\n", | |
" effect_iso3, \n", | |
" effect_ln_TFR,\n", | |
" int_wghts,\n", | |
" kernel_results.is_accepted,\n", | |
" loss,\n", | |
" ])\n", | |
" effect_iso3_samples[t, :] = effect_iso3_val \n", | |
" effect_ln_TFR_samples[t] = ln_tfr_val[0] \n", | |
" effect_int_samples[t] = int_val\n", | |
" num_accepted+= is_accepted_val\n", | |
" loss_history[t] = loss_val\n", | |
" if (t % 10 == 0):\n", | |
" print(\"Iteration: {} Loss: {:.3f},ln_TFR:{:.3f}, intercept:{:.3f}\".\n", | |
" format(t, loss_val, ln_tfr_val[0], int_val))" | |
] | |
} | |
], | |
"metadata": { | |
"kernelspec": { | |
"display_name": "Python 3", | |
"language": "python", | |
"name": "python3" | |
}, | |
"language_info": { | |
"codemirror_mode": { | |
"name": "ipython", | |
"version": 3 | |
}, | |
"file_extension": ".py", | |
"mimetype": "text/x-python", | |
"name": "python", | |
"nbconvert_exporter": "python", | |
"pygments_lexer": "ipython3", | |
"version": "3.6.5" | |
} | |
}, | |
"nbformat": 4, | |
"nbformat_minor": 2 | |
} |
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